Mastermind

Create a simple version of the board game: Mastermind.

It must be possible to:

choose the number of colors will be used in the game (2 - 20)
choose the color code length (4 - 10)
choose the maximum number of guesses the player has (7 - 20)
choose whether or not will be repeated colors in the code

The (computer program) game should display all the player guesses and the results of that guess.

Display (just an idea):

Feature	Graphic Version	Text Version
Player guess	Colored circles	Alphabet letters
Correct color & position	Black circle	X
Correct color	White circle	O
None	Gray circle	-

A text version example: 1: ADEF - XXO-
Translates to:
first guess;
the four colors(ADEF);
result: two correct colors and spot, one correct color/wrong spot one color is not in the code.

Happy coding!

Related tasks

Ada

Works with: Ada version 2012

<lang Ada>with Ada.Text_IO; with Ada.Numerics.Discrete_Random; with Ada.Strings.Fixed; with Ada.Containers.Ordered_Sets;

use Ada.Strings.Fixed;

procedure MasterMind is

  subtype Color_Number is Positive range 2 .. 20;
  subtype Code_Size is Positive range 4 .. 10;
  subtype Guesses_Number is Positive range 7 .. 20;
  subtype Color is Character range 'A' .. 'T';

  function Hint(correct, guess : in String) return String
  is
     Xs : Natural := 0;
     Os : Natural := 0;
     to_display : String(1 .. correct'Length) := (others => '-');
  begin
     for I in guess'Range loop
        if guess(I) = correct(I) then
           Xs := Xs + 1;
           to_display(I) := 'X';
        end if;
     end loop;
     for I in guess'Range loop
        if to_display(I) = '-' then
           for J in correct'Range loop
              if J /= I and to_display(J) /= 'X' and correct(J) = guess(I) then
                 Os := Os + 1;
                 exit;
              end if;
           end loop;
        end if;
     end loop;
     return Xs * 'X' & Os * 'O' & (guess'Length - Xs - Os) * '-';
  end Hint;

  generic
     type Data is (<>);
  function Input(message : in String) return Data;
  -- Input will loop until a correct value is given by the user.
  -- For each wrong input, the program will prompt the range of expected values.

  function Input(message : in String) return Data is
  begin
     loop
        Ada.Text_IO.Put(message);
        declare
           S : constant String := Ada.Text_IO.Get_Line;
        begin
           return Data'Value(S);
        exception
           when Constraint_Error =>
              Ada.Text_IO.New_Line;
              Ada.Text_IO.Put_Line("Invalid input!");
              Ada.Text_IO.Put_Line
                ("Expected values in range:"
                 & Data'First'Img & " .." & Data'Last'Img);
              Ada.Text_IO.New_Line;
        end;
     end loop;
  end;

  function Input_Color_Number is new Input(Color_Number);
  function Input_Code_Size is new Input(Code_Size);
  function Input_Guesses_Number is new Input(Guesses_Number);
  function Input_Boolean is new Input(Boolean);

  CN : constant Color_Number := Input_Color_Number("How many colors? ");
  GN : constant Guesses_Number := Input_Guesses_Number("How many guesses? ");
  CS : constant Code_Size := Input_Code_Size("Size of the code? ");
  repeats : Boolean := Input_Boolean("With repeats? ");
  -- Not constant: if Color < Code_Size, we will have repetitions anyway.

  subtype Actual_Colors is Color range Color'First .. Color'Val(Color'Pos(Color'First) + CN - 1);
  package Actual_Colors_Sets is new Ada.Containers.Ordered_Sets(Element_Type => Actual_Colors);

  package Color_Random is new Ada.Numerics.Discrete_Random(Result_Subtype => Actual_Colors);
  generator : Color_Random.Generator;

  function Random return String
  is
     C : String(1 .. CS);
     seen : Actual_Colors_Sets.Set;
  begin
     for I in C'Range loop
        C(I) := Color_Random.Random(generator);
        while (not repeats) and seen.Contains(C(I)) loop
           C(I) := Color_Random.Random(generator);
        end loop;
        seen.Include(C(I));
     end loop;
     return C;
  end Random;

  function Get_Code return String is
  begin
     loop
        Ada.Text_IO.Put("> ");
        declare
           input : constant String := Ada.Text_IO.Get_Line;
        begin
           if input'Length /= CS then
              raise Constraint_Error;
           end if;
           for C of input loop
              if C not in Actual_Colors then
                 raise Constraint_Error;
              end if;
           end loop;
           return input;
        exception
           when Constraint_Error =>
              Ada.Text_IO.New_Line;
              Ada.Text_IO.Put_Line("Invalid input!");
              Ada.Text_IO.New_Line;
        end;
     end loop;
  end Get_Code;

  found : Boolean := False;

begin

  if (not repeats) and (CN < CS) then
     Ada.Text_IO.Put_Line("Not enough colors! Using repeats anyway.");
     repeats := True;
  end if;

  Color_Random.Reset(generator);

  declare
     answer : constant String := Random;
     previous : array(1 .. GN) of String(1 .. CS*2);
  begin
     for I in 1 .. GN loop
        declare
           guess : constant String := Get_Code;
        begin
           if guess = answer then
              Ada.Text_IO.Put_Line("You won, congratulations!");
              found := True;
           else
              previous(I) := guess & Hint(answer, guess);
              Ada.Text_IO.Put_Line(44 * '-');
              for J in 1 .. I loop
                 Ada.Text_IO.Put_Line
                   (previous(J)(1 .. CS)
                    & " => " & previous(J)(CS+1 .. previous(J)'Last));
              end loop;
              Ada.Text_IO.Put_Line(44 * '-');
              Ada.Text_IO.New_Line;
           end if;
        end;
        exit when found;
     end loop;
     if not found then
        Ada.Text_IO.Put_Line("You lost, sorry! The answer was: " & answer);
     end if;
  end;

end MasterMind; </lang>

Output:

How many colors? 9
How many guesses? 4

Invalid input!
Expected values in range: 7 .. 20

How many guesses? 20
Size of the code? 4
With repeats? False
> ABCD
--------------------------------------------
ABCD => XOO-
--------------------------------------------

> EFGH
--------------------------------------------
ABCD => XOO-
EFGH => O---
--------------------------------------------

> ABCE
--------------------------------------------
ABCD => XOO-
EFGH => O---
ABCE => XOO-
--------------------------------------------

> ABCF
--------------------------------------------
ABCD => XOO-
EFGH => O---
ABCE => XOO-
ABCF => XOO-
--------------------------------------------

> ABCG
--------------------------------------------
ABCD => XOO-
EFGH => O---
ABCE => XOO-
ABCF => XOO-
ABCG => XXOO
--------------------------------------------

> ACBG
You won, congratulations!

AutoHotkey

<lang AutoHotkey>w := h := 32, maxRows := 10, numPegs := 8 ww := floor(w/2-2), hh := floor(h/2-2) grid := [], dx := w*4.5 gosub, Decode

Gui, Font, S18, Consolas loop, 4 { i := A_Index-1 Gui, add, button, % "x" (Mod(i, 4)?"+0":"30") " y" . (Mod(i, 4)?"10" : "10") " w" w " h" h " vGoal" A_Index , ? }

Gui, Add, Text, % "section x30 h1 0x1000 w" w*6 loop, % maxRows { Gui, Font, S18, consolas row := maxRows - A_Index + 1 loop 4 { col := A_Index, i:= col-1 Gui, add, button, % "x" (Mod(i, 4)?"+0":"s") " y" (Mod(i, 4)?"p":"+2") . " w" w " h" h " vButton" row "_" col " gButton" } Gui, Font, S13, wingdings 2 loop 2 { col := A_Index, i:= col-1 Gui, add, text, % "x" (Mod(i,2)?"+1":"s+" dx) " y" (Mod(i,2)?"p":"p+1") . " w" ww " h" hh " vKeyPeg" row "_" col, % Chr(167) } loop 2 { col := A_Index+2, i:= col-1 Gui, add, text, % "x" (Mod(i,2)?"+1":"s+" dx) " y" (Mod(i,2)?"p":"+1") . " w" ww " h" hh " vKeyPeg" row "_" col, % Chr(167) } Gui, Add, Text, % "section xs h1 0x1000 w" w*6 " y+4" } Gui, Font, S12, consolas Gui, add, Button, % "xs y+10 gSubmit w" W*2 , Submit Gui, add, Button, % "x+0 gResetMM w" W*2, Reset Gui, add, Checkbox, % "x+4 vNoDup", No`nDuplicates Gui, Font, S18 for i, v in pegs Gui, add, Radio, % "x" (!Mod(i-1, 4)?"10":"+10") " h" h " w" w+20 " vRadio" A_Index, % v Gui, show Row := 1 return

-----------------------------------------------------------------------

GuiClose: ExitApp return

-----------------------------------------------------------------------

Decode: Gui, Submit, NoHide pegs:=[], goal := [], usedPeg :=[] pool := ["😺","🎃","🧨","⚽","😀","☠","👽","❄","🙉","💗" ,"💥","🖐","🏈","🎱","👁","🗨","🤙","👄","🐶","🐴" ,"🦢","🐍","🐞","💣","🐪","🐘","🐰","🐸","🌴","🏀"]

loop, % numPegs { Random, rnd, 1, % pool.count() pegs[A_Index] := pool.RemoveAt(rnd) } i := 1 while (goal.count()<4) { Random, rnd, 1, % pegs.count() if (NoDup && usedPeg[pegs[rnd]]) continue goal[i++] := pegs[rnd] usedPeg[pegs[rnd]] := true } return

-----------------------------------------------------------------------

Button: if GameEnd return

Gui, Submit, NoHide RegExMatch(A_GuiControl, "Button(\d+)_(\d+)", m) if (m1 <> row) { thisPeg := Grid[m1, m2] for i, v in pegs if (v=thisPeg) GuiControl,, Radio%i%, 1 GuiControl,, % "Button" row "_" m2, % thisPeg Grid[row,m2] := thisPeg } else { loop, % pegs.count() if Radio%A_Index% GuiControl,, % A_GuiControl , % grid[m1, m2] := pegs[A_Index] } return

-----------------------------------------------------------------------

Submit: if (grid[row].count()<4) || GameEnd return

Gui, submit, NoHide Ans := [], FIP := [], inGoal := [] CIP := CNP := 0, KeyPeg := 1

for i, G in Goal inGoal[G] := (inGoal[G] ? inGoal[G] : 0) +1 ; save inGoal loop, 4 Ans[A_Index] := Grid[row, A_Index] ; save Ans for i, A in Ans if (goal[A_Index] = A) CIP++, FIP.push(i), inGoal[A]:=inGoal[A] -1 ; Correct In Place, inGoal-- for i, v in FIP Ans.RemoveAt(v-i+1) ; remove Correct In Place from Answers for i, A in Ans if (inGoal[A] > 0) CNP++, inGoal[A] := inGoal[A] -1 ; Correct Not in Place loop % CIP GuiControl,, % "KeyPeg" row "_" KeyPeg++, % Chr(82) ; "✔" loop % CNP GuiControl,, % "KeyPeg" row "_" KeyPeg++, % Chr(83) ; "X"

if (CIP=4 || row=maxRows) { loop 4 GuiControl,, Goal%A_Index%, % Goal[A_Index] MsgBox % CIP = 4 ? "You Win" : "You lose" GameEnd := true } Row++ return

-----------------------------------------------------------------------

LAlt:: ; peak at solution (for troubleshooting purposes only!) loop 4 GuiControl,, Goal%A_Index%, % Goal[A_Index] While GetKeyState("Lalt", "P") continue loop 4 GuiControl,, Goal%A_Index%, % "?" return

-----------------------------------------------------------------------

ResetMM: Grid :=[], GameEnd:= false loop, 4 { Random, rnd, 1, % pegs.count() goal[A_Index] := pegs[rnd] GuiControl,, Goal%A_Index%, ? }

loop, % maxRows { row := maxRows - A_Index + 1 loop 4 { col := A_Index GuiControl,, % "KeyPeg" row "_" col, % Chr(167) ; "O" GuiControl,, % "Button" row "_" col } } gosub Decode loop, 8 GuiControl,, Radio%A_Index%, % pegs[A_Index] return

-----------------------------------------------------------------------</lang>

C++

<lang cpp>#include <iostream>

include <algorithm>
include <ctime>
include <string>
include <vector>

typedef std::vector<char> vecChar;

class master { public:

   master( size_t code_len, size_t clr_count, size_t guess_count, bool rpt ) {
       std::string color = "ABCDEFGHIJKLMNOPQRST";

       if( code_len < 4 ) code_len = 4; else if( code_len > 10 ) code_len = 10;
       if( !rpt && clr_count < code_len ) clr_count = code_len; 
       if( clr_count < 2 ) clr_count = 2; else if( clr_count > 20 ) clr_count = 20;
       if( guess_count < 7 ) guess_count = 7; else if( guess_count > 20 ) guess_count = 20;
       
       codeLen = code_len; colorsCnt = clr_count; guessCnt = guess_count; repeatClr = rpt;

       for( size_t s = 0; s < colorsCnt; s++ ) {
           colors.append( 1, color.at( s ) );
       }
   }
   void play() {
       bool win = false;
       combo = getCombo();

       while( guessCnt ) {
           showBoard();
           if( checkInput( getInput() ) ) {
               win = true;
               break;
           }
           guessCnt--;
       }
       if( win ) {
           std::cout << "\n\n--------------------------------\n" <<
               "Very well done!\nYou found the code: " << combo <<
               "\n--------------------------------\n\n";
       } else {
           std::cout << "\n\n--------------------------------\n" <<
               "I am sorry, you couldn't make it!\nThe code was: " << combo <<
               "\n--------------------------------\n\n";
       }
   }

private:

   void showBoard() {
       vecChar::iterator y;
       for( int x = 0; x < guesses.size(); x++ ) {
           std::cout << "\n--------------------------------\n";
           std::cout << x + 1 << ": ";
           for( y = guesses[x].begin(); y != guesses[x].end(); y++ ) {
               std::cout << *y << " ";
           }

           std::cout << " :  ";
           for( y = results[x].begin(); y != results[x].end(); y++ ) {
               std::cout << *y << " ";
           }

           int z = codeLen - results[x].size();
           if( z > 0 ) {
               for( int x = 0; x < z; x++ ) std::cout << "- ";
           }
       }
       std::cout << "\n\n";
   }
   std::string getInput() {
       std::string a;
       while( true ) {
           std::cout << "Enter your guess (" << colors << "): ";
           a = ""; std::cin >> a;
           std::transform( a.begin(), a.end(), a.begin(), ::toupper );
           if( a.length() > codeLen ) a.erase( codeLen );
           bool r = true;
           for( std::string::iterator x = a.begin(); x != a.end(); x++ ) {
               if( colors.find( *x ) == std::string::npos ) {
                   r = false;
                   break;
               }
           }
           if( r ) break;
       }
       return a;
   }
   bool checkInput( std::string a ) {
       vecChar g;
       for( std::string::iterator x = a.begin(); x != a.end(); x++ ) {
           g.push_back( *x );
       }
       guesses.push_back( g );
       
       int black = 0, white = 0;
       std::vector<bool> gmatch( codeLen, false );
       std::vector<bool> cmatch( codeLen, false );

       for( int i = 0; i < codeLen; i++ ) {
           if( a.at( i ) == combo.at( i ) ) {
               gmatch[i] = true;
               cmatch[i] = true;
               black++;
           }
       }

       for( int i = 0; i < codeLen; i++ ) {
           if (gmatch[i]) continue;
           for( int j = 0; j < codeLen; j++ ) {
               if (i == j || cmatch[j]) continue;
               if( a.at( i ) == combo.at( j ) ) {
                   cmatch[j] = true;
                   white++;
                   break;
               }
           }
       }
      
       vecChar r;
       for( int b = 0; b < black; b++ ) r.push_back( 'X' );
       for( int w = 0; w < white; w++ ) r.push_back( 'O' );
       results.push_back( r );

       return ( black == codeLen );
   }
   std::string getCombo() {
       std::string c, clr = colors;
       int l, z;

       for( size_t s = 0; s < codeLen; s++ ) {
           z = rand() % ( int )clr.length();
           c.append( 1, clr[z] );
           if( !repeatClr ) clr.erase( z, 1 );
       }
       return c;
   }

   size_t codeLen, colorsCnt, guessCnt;
   bool repeatClr;
   std::vector<vecChar> guesses, results;
   std::string colors, combo;

};

int main( int argc, char* argv[] ) {

   srand( unsigned( time( 0 ) ) );
   master m( 4, 8, 12, false );
   m.play();
   return 0;

} </lang>

Output:

Enter your guess (ABCDEFGH): gbda

--------------------------------
1: A B C D  :  X O O -
--------------------------------
2: A A A E  :  O - - -
--------------------------------
3: E E E E  :  - - - -
--------------------------------
4: B B B C  :  X - - -
--------------------------------
5: D B A F  :  X O O -
--------------------------------
6: G B D A  :  X X X -

Enter your guess (ABCDEFGH): hbda


--------------------------------
Very well done!
You found the code: HBDA
--------------------------------

EasyLang

Run it

<lang>intvars col[] = [ 902 990 171 229 960 808 ] len code[] 4 len guess[] 4

subr init_vars

 row = 7

. func draw_rate r black white . .

 for j range 2
   for c range 2
     move c * 3.5 + 76.5 r * 11.5 + 10.4 + j * 3.5
     if black > 0
       color 000
       circle 1.4
       black -= 1
     elif white > 0
       color 999
       circle 1.4
       white -= 1
     else
       color 310
       circle 0.7
     .
   .
 .

. func show_code . .

 color 531
 move 27 0
 rect 46 8
 for i range 4
   move i * 8 + 33 3
   color col[code[i]]
   circle 2
 .

. func draw_guess . .

 for c range 4
   move c * 12 + 25 row * 11.5 + 12
   color col[guess[c]]
   circle 3.8
 .

. func next_row . .

 color 420
 linewidth 11
 move 22 row * 11.5 + 12
 line 65 row * 11.5 + 12
 call draw_guess
 move 78.5 row * 11.5 + 12
 color 310
 circle 5.0
 move 75.7 row * 11.5 + 9.8
 color 753
 text "OK"

. func rate . .

 move 78.5 row * 11.5 + 12
 color 531
 circle 5.2
 c[] = code[]
 g[] = guess[]
 for i range 4
   if c[i] = g[i]
     black += 1
     c[i] = -1
     g[i] = -2
   .
 .
 for i range 4
   for j range 4
     if c[i] = g[j]
       white += 1
       c[i] = -1
       g[j] = -2
     .
   .
 .
 call draw_rate row black white
 color 531
 linewidth 12
 move 22 row * 11.5 + 12
 line 65 row * 11.5 + 12
 call draw_guess
 row -= 1
 if black = 4
   row = -1
 .
 if row = -1
   call show_code
   timer 1
 else
   call next_row
 .

. on timer

 row = -2

. func new . .

 call init_vars
 for i range 4
   code[i] = random 6
 .
 color 531
 move 15 10
 rect 70 80
 linewidth 10
 move 10 5
 line 10 95
 line 90 95
 line 90 5
 line 10 5
 color 310
 linewidth 7
 move 33 3.5
 line 63 3.5
 move 35 1
 color 864
 textsize 4.5
 text "Mastermind"
 color 310
 linewidth 0.5
 move 15 10
 line 15 96
 move 72 10
 line 72 96
 move 85 10
 line 85 96
 for r range 8
   for c range 4
     move c * 12 + 25 r * 11.5 + 12
     circle 2
   .
   call draw_rate r 0 0
 .
 for i range 4
   guess[i] = i
 .
 call next_row

. func do_move . .

 c = floor ((mouse_x - 20) / 12)
 guess[c] = (guess[c] + 1) mod 6
 call draw_guess

. on mouse_down

 if row = -2
   call new
 elif mouse_y > row * 11.5 + 7 and mouse_y < row * 11.5 + 17
   if mouse_x > 20 and mouse_x < 66
     call do_move
   elif mouse_x > 72 and mouse_x < 85
     call rate
   .
 .

. call new</lang>

Go

<lang Go>package main

import ( "errors" "flag" "fmt" "log" "math/rand" "strings" "time" )

func main() { log.SetPrefix("mastermind: ") log.SetFlags(0) colours := flag.Int("colours", 6, "number of colours to use (2-20)") flag.IntVar(colours, "colors", 6, "alias for colours") holes := flag.Int("holes", 4, "number of holes (the code length, 4-10)") guesses := flag.Int("guesses", 12, "number of guesses allowed (7-20)") unique := flag.Bool("unique", false, "disallow duplicate colours in the code") flag.Parse()

rand.Seed(time.Now().UnixNano()) m, err := NewMastermind(*colours, *holes, *guesses, *unique) if err != nil { log.Fatal(err) } err = m.Play() if err != nil { log.Fatal(err) } }

type mastermind struct { colours int holes int guesses int unique bool

code string past []string // history of guesses scores []string // history of scores }

func NewMastermind(colours, holes, guesses int, unique bool) (*mastermind, error) { if colours < 2 || colours > 20 { return nil, errors.New("colours must be between 2 and 20 inclusive") } if holes < 4 || holes > 10 { return nil, errors.New("holes must be between 4 and 10 inclusive") } if guesses < 7 || guesses > 20 { return nil, errors.New("guesses must be between 7 and 20 inclusive") } if unique && holes > colours { return nil, errors.New("holes must be > colours when using unique") }

return &mastermind{ colours: colours, holes: holes, guesses: guesses, unique: unique, past: make([]string, 0, guesses), scores: make([]string, 0, guesses), }, nil }

func (m *mastermind) Play() error { m.generateCode() fmt.Printf("A set of %s has been selected as the code.\n", m.describeCode(m.unique)) fmt.Printf("You have %d guesses.\n", m.guesses) for len(m.past) < m.guesses { guess, err := m.inputGuess() if err != nil { return err } fmt.Println() m.past = append(m.past, guess) str, won := m.scoreString(m.score(guess)) if won { plural := "es" if len(m.past) == 1 { plural = "" } fmt.Printf("You found the code in %d guess%s.\n", len(m.past), plural) return nil } m.scores = append(m.scores, str) m.printHistory() fmt.Println() } fmt.Printf("You are out of guesses. The code was %s.\n", m.code) return nil }

const charset = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" const blacks = "XXXXXXXXXX" const whites = "OOOOOOOOOO" const nones = "----------"

func (m *mastermind) describeCode(unique bool) string { ustr := "" if unique { ustr = " unique" } return fmt.Sprintf("%d%s letters (from 'A' to %q)", m.holes, ustr, charset[m.colours-1], ) }

func (m *mastermind) printHistory() { for i, g := range m.past { fmt.Printf("-----%s---%[1]s--\n", nones[:m.holes]) fmt.Printf("%2d: %s : %s\n", i+1, g, m.scores[i]) } }

func (m *mastermind) generateCode() { code := make([]byte, m.holes) if m.unique { p := rand.Perm(m.colours) for i := range code { code[i] = charset[p[i]] } } else { for i := range code { code[i] = charset[rand.Intn(m.colours)] } } m.code = string(code) //log.Printf("code is %q", m.code) }

func (m *mastermind) inputGuess() (string, error) { var input string for { fmt.Printf("Enter guess #%d: ", len(m.past)+1) if _, err := fmt.Scanln(&input); err != nil { return "", err } input = strings.ToUpper(strings.TrimSpace(input)) if m.validGuess(input) { return input, nil } fmt.Printf("A guess must consist of %s.\n", m.describeCode(false)) } }

func (m *mastermind) validGuess(input string) bool { if len(input) != m.holes { return false } for i := 0; i < len(input); i++ { c := input[i] if c < 'A' || c > charset[m.colours-1] { return false } } return true }

func (m *mastermind) score(guess string) (black, white int) { scored := make([]bool, m.holes) for i := 0; i < len(guess); i++ { if guess[i] == m.code[i] { black++ scored[i] = true } } for i := 0; i < len(guess); i++ { if guess[i] == m.code[i] { continue } for j := 0; j < len(m.code); j++ { if i != j && !scored[j] && guess[i] == m.code[j] { white++ scored[j] = true } } } return }

func (m *mastermind) scoreString(black, white int) (string, bool) { none := m.holes - black - white return blacks[:black] + whites[:white] + nones[:none], black == m.holes }</lang>

Output (using Knuth's five-guess algorithm):

A set of 4 letters (from 'A' to 'F') has been selected as the code.
You have 12 guesses.
[... output of first guesses omitted ...]
Enter guess #4: FEDE

------------------
 1:  AABB : ----
------------------
 2:  FFED : XOOO
------------------
 3:  DFDF : XO--
------------------
 4:  FEDE : XOOO

Enter guess #5: EFFE

You found the code in 5 guesses.

JavaScript

You can try it here.

<lang javascript> class Mastermind {

 constructor() {
   this.colorsCnt;
   this.rptColors;
   this.codeLen;
   this.guessCnt;
   this.guesses;
   this.code;
   this.selected;
   this.game_over;
   this.clear = (el) => {
     while (el.hasChildNodes()) {
       el.removeChild(el.firstChild);
     }
   };
   this.colors = ["🤡", "👹", "👺", "👻", "👽", "👾", "🤖", "🐵", "🐭",
     "🐸", "🎃", "🤠", "☠️", "🦄", "🦇", "🛸", "🎅", "👿", "🐲", "🦋"
   ];
 }

 newGame() {
   this.selected = null;
   this.guessCnt = parseInt(document.getElementById("gssCnt").value);
   this.colorsCnt = parseInt(document.getElementById("clrCnt").value);
   this.codeLen = parseInt(document.getElementById("codeLen").value);
   if (this.codeLen > this.colorsCnt) {
     document.getElementById("rptClr").selectedIndex = 1;
   }
   this.rptColors = document.getElementById("rptClr").value === "yes";
   this.guesses = 0;
   this.game_over = false;
   const go = document.getElementById("gameover");
   go.innerText = "";
   go.style.visibility = "hidden";
   this.clear(document.getElementById("code"));
   this.buildPalette();
   this.buildPlayField();
 }

 buildPalette() {
   const pal = document.getElementById("palette"),
     z = this.colorsCnt / 5,
     h = Math.floor(z) != z ? Math.floor(z) + 1 : z;
   this.clear(pal);
   pal.style.height = `${44 * h + 3 * h}px`;
   const clrs = [];
   for (let c = 0; c < this.colorsCnt; c++) {
     clrs.push(c);
     const b = document.createElement("div");
     b.className = "bucket";
     b.clr = c;
     b.innerText = this.colors[c];
     b.addEventListener("click", () => {
       this.palClick(b);
     });
     pal.appendChild(b);
   }
   this.code = [];
   while (this.code.length < this.codeLen) {
     const r = Math.floor(Math.random() * clrs.length);
     this.code.push(clrs[r]);
     if (!this.rptColors) {
       clrs.splice(r, 1);
     }
   }
 }

 buildPlayField() {
   const brd = document.getElementById("board");
   this.clear(brd);
   const w = 49 * this.codeLen + 7 * this.codeLen + 5;
   brd.active = 0;
   brd.style.width = `${w}px`;
   document.querySelector(".column").style.width = `${w + 20}px`;
   this.addGuessLine(brd);
 }

 addGuessLine(brd) {
   const z = document.createElement("div");
   z.style.clear = "both";
   brd.appendChild(z);
   brd.active += 10;
   for (let c = 0; c < this.codeLen; c++) {
     const d = document.createElement("div");
     d.className = "bucket";
     d.id = `brd${brd.active+ c}`;
     d.clr = -1;
     d.addEventListener("click", () => {
       this.playClick(d);
     })
     brd.appendChild(d);
   }
 }

 palClick(bucket) {
   if (this.game_over) return;
   if (null === this.selected) {
     bucket.classList.add("selected");
     this.selected = bucket;
     return;
   }
   if (this.selected !== bucket) {
     this.selected.classList.remove("selected");
     bucket.classList.add("selected");
     this.selected = bucket;
     return;
   }
   this.selected.classList.remove("selected");
   this.selected = null;
 }

 vibrate() {
   const brd = document.getElementById("board");
   let timerCnt = 0;
   const exp = setInterval(() => {
     if ((timerCnt++) > 60) {
       clearInterval(exp);
       brd.style.top = "0px";
       brd.style.left = "0px";
     }
     let x = Math.random() * 4,
       y = Math.random() * 4;
     if (Math.random() < .5) x = -x;
     if (Math.random() < .5) y = -y;
     brd.style.top = y + "px";
     brd.style.left = x + "px";
   }, 10);
 }

 playClick(bucket) {
   if (this.game_over) return;
   if (this.selected) {
     bucket.innerText = this.selected.innerText;
     bucket.clr = this.selected.clr;
   } else {
     this.vibrate();
   }
 }

 check() {
   if (this.game_over) return;
   let code = [];
   const brd = document.getElementById("board");
   for (let b = 0; b < this.codeLen; b++) {
     const h = document.getElementById(`brd${brd.active + b}`).clr;
     if (h < 0) {
       this.vibrate();
       return;
     }
     code.push(h);
   }
   this.guesses++;
   if (this.compareCode(code)) {
     this.gameOver(true);
     return;
   }
   if (this.guesses >= this.guessCnt) {
     this.gameOver(false);
     return;
   }
   this.addGuessLine(brd);
 }

 compareCode(code) {
   let black = 0,
     white = 0,
     b_match = new Array(this.codeLen).fill(false),
     w_match = new Array(this.codeLen).fill(false);
   for (let i = 0; i < this.codeLen; i++) {
     if (code[i] === this.code[i]) {
       b_match[i] = true;
       w_match[i] = true;
       black++;
     }
   }
   for (let i = 0; i < this.codeLen; i++) {
     if (b_match[i]) continue;
     for (let j = 0; j < this.codeLen; j++) {
       if (i == j || w_match[j]) continue;
       if (code[i] === this.code[j]) {
         w_match[j] = true;
         white++;
         break;
       }
     }
   }
   const brd = document.getElementById("board");
   let d;
   for (let i = 0; i < black; i++) {
     d = document.createElement("div");
     d.className = "pin";
     d.style.backgroundColor = "#a00";
     brd.appendChild(d);
   }
   for (let i = 0; i < white; i++) {
     d = document.createElement("div");
     d.className = "pin";
     d.style.backgroundColor = "#eee";
     brd.appendChild(d);
   }
   return (black == this.codeLen);
 }

 gameOver(win) {
   if (this.game_over) return;
   this.game_over = true;
   const cd = document.getElementById("code");
   for (let c = 0; c < this.codeLen; c++) {
     const d = document.createElement("div");
     d.className = "bucket";
     d.innerText = this.colors[this.code[c]];
     cd.appendChild(d);
   }
   const go = document.getElementById("gameover");
   go.style.visibility = "visible";
   go.innerText = win ? "GREAT!" : "YOU FAILED!";
   const i = setInterval(() => {
     go.style.visibility = "hidden";
     clearInterval(i);
   }, 3000);
 }

} const mm = new Mastermind(); document.getElementById("newGame").addEventListener("click", () => {

 mm.newGame()

}); document.getElementById("giveUp").addEventListener("click", () => {

 mm.gameOver();

}); document.getElementById("check").addEventListener("click", () => {

 mm.check()

}); </lang>

To test you'll need a HTML file

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <link rel="stylesheet" href="./css/style.css" type="text/css">
  <title>Mastermind</title>
</head>
<body>
  <div id="gameover"></div>
  <div class="column">
    <div id="board" style="position: relative"></div>
    <div style="clear: both"> </div>
    <button id="check" style="margin-top:20px">Check!</button>
    <button id="giveUp">Give up!</button>
    <div id="code" style="margin-top: 40px"></div>
  </div>
  <div class="columnS">
    <div id="ctrls">
      <label for="clrCnt">Colors count:</label>
      <input type="number" id="clrCnt" max="20" min="2" value="6"></input>
      <br />
      <label for="codeLen">Code length:</label>
      <input type="number" id="codeLen" max="10" min="4" value="4"></input>
      <br />
      <label for="gssCnt">Guesses count:</label>
      <input type="number" id="gssCnt" max="20" min="7" value="12"></input>
      <br />
      <label for="rptClr">Repeat colors:</label>
      <select id="rptClr">
        <option value="no">No</option>
        <option value="yes">Yes</option>
      </select>
      <button id="newGame" style="width: 100%">New game</button>
    </div>
    <div id="palette"></div>
  </div>
  <script src="./src/index.js" type="module"></script>
</body>
</html>

And a CSS file

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  user-select: none;
}
body {
  background-color: #222;
  text-align: left
}
button {
  width: 101px;
  height: 26px;
  background-color: #444;
  color: #ddd;
  border: 1px solid #333;
  border-radius: 4px;
}
input,
select {
  float: right;
  width: 60px;
  height: 24px;
  margin-top: 6px;
  font-size: 20px;
}
#palette {
  margin-top: 40px;
  width: 233px;
  border-radius: 5px;
  border: 1px solid #fff;
}
#ctrls {
  border-radius: 5px;
  border: 1px solid #fff;
  padding: 10px;
  font-size: 20px;
  width: 233px;
  line-height: 36px;
  color: #fff;
}
#gameover {
  position: absolute;
  top: 90px;
  left: 0;
  font-size: 100px;
  text-align: center;
  color: rgb(248, 143, 4);
  background: rgba(34, 34, 34, .8);
  padding: 10px;
  z-index: 999;
}
.column,
.columnS {
  float: left;
  width: 249px;
  margin: 30px;
}
.columnS {
  width: 300px;
  margin-left: 0;
}
.bucket {
  float: left;
  width: 42px;
  height: 42px;
  line-height: 40px;
  font-size: 26px;
  border: 2px solid #fff;
  border-radius: 3px;
  margin: 2px;
  cursor: pointer;
}
.selected {
  border: 2px solid #d00;
}
.pin {
  float: left;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  margin: 2px;
}

Julia

GUI version, uses the Gtk toolkit. <lang julia>using Gtk, Colors, Cairo, Graphics

struct Guess

   code::Vector{Color}
   guess::Vector{Color}
   hint::Vector{Color}

end

function Guess(code, guess)

   len = length(code)
   hints = fill(colorant"gray", len) # gray default
   for (i, g) in enumerate(guess), (j, c) in enumerate(code)
       if g == c
           if i == j
               hints[i] = colorant"black"
           elseif hints[i] != colorant"black"
               hints[i] = colorant"white"
           end
       end
   end
   g = Guess([c for c in code], [c for c in guess], [c for c in hints])

end

tovec(guess) = [x for x in [guess.code; guess.guess; guess.hint]]

function mastermindapp()

   allu(s) = length(unique(s)) == length(s)
   ccode(c, n, rok) = while true a = rand(c, n); if rok || allu(a) return a end end

   numcolors, codelength, maxguesses, allowrep, gameover = 10, 4, 10, false, false
   colors = distinguishable_colors(numcolors)
   code = ccode(colors, numcolors, allowrep)
   guesshistory = Vector{Guess}()
   
   win = GtkWindow("Mastermind Game", 900, 750) |> (GtkFrame() |> (box = GtkBox(:v)))  
   settingsbox = GtkBox(:h)
   playtoolbar = GtkToolbar()

   setcolors = GtkScale(false, 4:20)
   set_gtk_property!(setcolors, :hexpand, true)
   adj = GtkAdjustment(setcolors)
   set_gtk_property!(adj, :value, 10)
   clabel = GtkLabel("Number of Colors")

   setcodelength = GtkScale(false, 4:10)
   set_gtk_property!(setcodelength, :hexpand, true)
   adj = GtkAdjustment(setcodelength)
   set_gtk_property!(adj, :value, 4)
   slabel = GtkLabel("Code Length")

   setnumguesses = GtkScale(false, 4:40)
   set_gtk_property!(setnumguesses, :hexpand, true)
   adj = GtkAdjustment(setnumguesses)
   set_gtk_property!(adj, :value, 10)
   nlabel = GtkLabel("Max Guesses")

   allowrepeatcolor = GtkScale(false, 0:1)
   set_gtk_property!(allowrepeatcolor, :hexpand, true)
   rlabel = GtkLabel("Allow Repeated Colors (0 = No)")

   newgame = GtkToolButton("New Game")
   set_gtk_property!(newgame, :label, "New Game")
   set_gtk_property!(newgame, :is_important, true)

   tryguess = GtkToolButton("Submit Current Guess")
   set_gtk_property!(tryguess, :label, "Submit Current Guess")
   set_gtk_property!(tryguess, :is_important, true)

   eraselast = GtkToolButton("Erase Last (Unsubmitted) Pick")
   set_gtk_property!(eraselast, :label, "Erase Last (Unsubmitted) Pick")
   set_gtk_property!(eraselast, :is_important, true)

   map(w->push!(settingsbox, w),[clabel, setcolors, slabel, setcodelength,
       nlabel, setnumguesses, rlabel, allowrepeatcolor])
   map(w->push!(playtoolbar, w),[newgame, tryguess, eraselast])
   
   scrwin = GtkScrolledWindow()
   can = GtkCanvas()
   set_gtk_property!(can, :expand, true)
   map(w -> push!(box, w),[settingsbox, playtoolbar, scrwin])
   push!(scrwin, can)

   currentguess = RGB[]
   guessesused = 0
   colorpositions = Point[]
   
   function newgame!(w)
       empty!(guesshistory)
       
       numcolors = Int(GAccessor.value(setcolors))
       codelength = Int(GAccessor.value(setcodelength))
       maxguesses = Int(GAccessor.value(setnumguesses))
       allowrep = Int(GAccessor.value(allowrepeatcolor))
       
       colors = distinguishable_colors(numcolors)
       code = ccode(colors, codelength, allowrep == 1)
       empty!(currentguess)
       currentneeded = codelength
       guessesused = 0
       gameover = false
       draw(can)
   end
   signal_connect(newgame!, newgame, :clicked)
      
   function saywon!()
       warn_dialog("You have WON the game!", win)
       gameover = true
   end

   function outofguesses!()
       warn_dialog("You have Run out of moves! Game over.", win)
       gameover = true    
   end
   
   can.mouse.button1press = @guarded (widget, event) -> begin
       if !gameover && (i = findfirst(p -> 
           sqrt((p.x - event.x)^2 + (p.y - event.y)^2) < 20,
               colorpositions)) != nothing
           if length(currentguess) < codelength
               if allowrep == 0 && !allu(currentguess)
                   warn_dialog("Please erase the duplicate color.", win)
               else
                   push!(currentguess, colors[i])
                   draw(can)
               end
           else
               warn_dialog("You need to submit this guess if ready.", win)
           end
       end
   end
   
   @guarded draw(can) do widget
       ctx = Gtk.getgc(can)
       select_font_face(ctx, "Courier", Cairo.FONT_SLANT_NORMAL, Cairo.FONT_WEIGHT_BOLD)
       fontpointsize = 12
       set_font_size(ctx, fontpointsize)
       workcolor = colorant"black"
       set_source(ctx, workcolor)
       move_to(ctx, 0, fontpointsize)
       show_text(ctx, "Color options: " * "-"^70)
       stroke(ctx)
       empty!(colorpositions)
       for i in 1:numcolors
           set_source(ctx, colors[i])
           circle(ctx, i * 40, 40, 20)
           push!(colorpositions, Point(i * 40, 40))
           fill(ctx)
       end
       set_gtk_property!(can, :expand, false) # kludge for good text overwriting
       move_to(ctx, 0, 80)
       set_source(ctx, workcolor)
       show_text(ctx, string(maxguesses - guessesused, pad = 2) * " moves remaining.")
       stroke(ctx)
       set_gtk_property!(can, :expand, true)
       for i in 1:codelength
           set_source(ctx, i > length(currentguess) ? colorant"lightgray" : currentguess[i])
           circle(ctx, i * 40, 110, 20)
           fill(ctx)
       end
       if length(guesshistory) > 0
           move_to(ctx, 0, 155)
           set_source(ctx, workcolor)
           show_text(ctx, "Past Guesses: " * "-"^70)
           for (i, g) in enumerate(guesshistory), (j, c) in enumerate(tovec(g)[codelength+1:end])
               x = j * 40 + (j > codelength ? 20 : 0)
               y = 150 + 40 * i
               set_source(ctx, c)
               circle(ctx, x, y, 20)
               fill(ctx)
           end
       end
       Gtk.showall(win)
   end

   function submitguess!(w)
       if length(currentguess) == length(code)
           g = Guess(code, currentguess)
           push!(guesshistory, g)
           empty!(currentguess)
           guessesused += 1
           draw(can)
           if all(i -> g.code[i] == g.guess[i], 1:length(code))
               saywon!()
           elseif guessesused > maxguesses
               outofguesses!()
           end
       end
   end
   signal_connect(submitguess!, tryguess, :clicked)

   function undolast!(w)
       if length(currentguess) > 0
           pop!(currentguess)
           draw(can)
       end
   end
   signal_connect(undolast!, eraselast, :clicked)

   newgame!(win)
   Gtk.showall(win)
  
   condition = Condition()
   endit(w) = notify(condition)
   signal_connect(endit, win, :destroy)
   showall(win)
   wait(condition)

end

mastermindapp() </lang>

Kotlin

Translation of: C++

<lang scala>// version 1.2.51

import java.util.Random

val rand = Random()

class Mastermind {

   private val codeLen: Int
   private val colorsCnt: Int
   private var guessCnt = 0
   private val repeatClr: Boolean

   private val colors: String
   private var combo = ""

   private val guesses = mutableListOf<CharArray>()
   private val results = mutableListOf<CharArray>()

   constructor(codeLen: Int, colorsCnt: Int, guessCnt: Int, repeatClr: Boolean) {
       val color = "ABCDEFGHIJKLMNOPQRST"
       this.codeLen = codeLen.coerceIn(4, 10)
       var cl = colorsCnt
       if (!repeatClr && cl < this.codeLen) cl = this.codeLen
       this.colorsCnt = cl.coerceIn(2, 20)       
       this.guessCnt = guessCnt.coerceIn(7, 20)    
       this.repeatClr = repeatClr
       this.colors = color.take(this.colorsCnt)
   }

   fun play() {
       var win = false
       combo = getCombo()
       while (guessCnt != 0) {
           showBoard()
           if (checkInput(getInput())) {
               win = true
               break
           }
           guessCnt--
       }
       println("\n\n--------------------------------")
       if (win) {
           println("Very well done!\nYou found the code: $combo")
       }
       else {
           println("I am sorry, you couldn't make it!\nThe code was: $combo")
       }
       println("--------------------------------\n")
   }

   private fun showBoard() {
       for (x in 0 until guesses.size) {
           println("\n--------------------------------")
           print("${x + 1}: ")
           for (y in guesses[x]) print("$y ")
           print(" :  ")
           for (y in results[x]) print("$y ")
           val z = codeLen - results[x].size
           if (z > 0) print("- ".repeat(z))
       }
       println("\n")
   }

   private fun getInput(): String {
       while (true) {
           print("Enter your guess ($colors): ")
           val a = readLine()!!.toUpperCase().take(codeLen)          
           if (a.all { it in colors } ) return a
       }
   }

   private fun checkInput(a: String): Boolean {
       guesses.add(a.toCharArray())
       var black = 0
       var white = 0
       val gmatch = BooleanArray(codeLen)
       val cmatch = BooleanArray(codeLen)
       for (i in 0 until codeLen) {
           if (a[i] == combo[i]) {
               gmatch[i] = true
               cmatch[i] = true
               black++
           }
       }
       for (i in 0 until codeLen) {
           if (gmatch[i]) continue
           for (j in 0 until codeLen) {
               if (i == j || cmatch[j]) continue
               if (a[i] == combo[j]) {
                   cmatch[j] = true
                   white++
                   break
               }
           }
       }   
       val r = mutableListOf<Char>()
       r.addAll("X".repeat(black).toList())
       r.addAll("O".repeat(white).toList())    
       results.add(r.toCharArray())
       return black == codeLen
   }

   private fun getCombo(): String {
       val c =  StringBuilder()
       val clr = StringBuilder(colors)
       for (s in 0 until codeLen) {
           val z = rand.nextInt(clr.length)
           c.append(clr[z])
           if (!repeatClr) clr.deleteCharAt(z)
       }
       return c.toString()
   }

}

fun main(args: Array<String>) {

   val m = Mastermind(4, 8, 12, false)
   m.play()

}</lang>

Sample input/output (showing last 2 guesses only):

Enter your guess (ABCDEFGH): hcgb

--------------------------------
1: A B C D  :  O - - - 
--------------------------------
2: E F G H  :  X O O - 
--------------------------------
3: E G F A  :  O O - - 
--------------------------------
4: G F E A  :  O O - - 
--------------------------------
5: F H G B  :  X X O - 
--------------------------------
6: F B G C  :  X O - - 
--------------------------------
7: F G A B  :  X O - - 
--------------------------------
8: A H G C  :  X O - - 
--------------------------------
9: G H D B  :  X O O - 
--------------------------------
10: H A G B  :  X X X - 
--------------------------------
11: H C G B  :  X X X - 

Enter your guess (ABCDEFGH): hegb


--------------------------------
Very well done!
You found the code: HEGB
--------------------------------

Lua

Based on C++ <lang lua> math.randomseed( os.time() ) local black, white, none, code = "X", "O", "-" local colors, codeLen, maxGuess, rept, alpha, opt = 6, 4, 10, false, "ABCDEFGHIJKLMNOPQRST", "" local guesses, results function createCode()

   code = ""
   local dic, a = ""
   for i = 1, colors do
       dic = dic .. alpha:sub( i, i )
   end
   for i = 1, codeLen do
       a = math.floor( math.random( 1, #dic ) )
       code = code .. dic:sub( a, a )
       if not rept then
           dic = dic:sub(1, a - 1 ) .. dic:sub( a + 1, #dic )
       end
   end

end function checkInput( inp )

   table.insert( guesses, inp )
   local b, w, fnd, str = 0, 0, {}, ""
   for bl = 1, codeLen do
       if inp:sub( bl, bl ) == code:sub( bl, bl ) then
           b = b + 1; fnd[bl] = true
       else
           for wh = 1, codeLen do
               if nil == fnd[bl] and wh ~= bl and inp:sub( wh, wh ) == code:sub( bl, bl ) then
                   w = w + 1; fnd[bl] = true
               end
           end
       end
   end
   for i = 1, b do str = str .. string.format( "%s ", black ) end
   for i = 1, w do str = str .. string.format( "%s ", white ) end
   for i = 1, 2 * codeLen - #str, 2 do str = str .. string.format( "%s ", none ) end
   table.insert( results, str )
   return b == codeLen

end function play()

   local err, win, r = true, false;
   for j = 1, colors do opt = opt .. alpha:sub( j, j ) end
   while( true ) do
       createCode(); guesses, results = {}, {}
       for i = 1, maxGuess do
           err = true;
           while( err ) do
               io.write( string.format( "\n-------------------------------\nYour guess (%s)?", opt ) )
               inp = io.read():upper(); 
               if #inp == codeLen then
                   err = false;
                   for k = 1, #inp do
                       if( nil == opt:find( inp:sub( k, k ) ) ) then 
                           err = true;
                           break;
                       end
                   end
               end
           end
           if( checkInput( inp ) ) then win = true; break
           else
               for l = 1, #guesses do
                   print( string.format( "%.2d: %s : %s", l, guesses[l], results[l] ) )
               end
           end
       end
       if win then print( "\nWell done!" )
       else print( string.format( "\nSorry, you did not crack the code --> %s!", code ) )
       end
       io.write( "Play again( Y/N )? " ); r = io.read()
       if r ~= "Y" and r ~= "y" then break end
   end

end --entry point --- if arg[1] ~= nil and tonumber( arg[1] ) > 1 and tonumber( arg[1] ) < 21 then colors = tonumber( arg[1] ) end if arg[2] ~= nil and tonumber( arg[2] ) > 3 and tonumber( arg[2] ) < 11 then codeLen = tonumber( arg[2] ) end if arg[3] ~= nil and tonumber( arg[3] ) > 6 and tonumber( arg[3] ) < 21 then maxGuess = tonumber( arg[3] ) end if arg[4] ~= nil and arg[4] == "true" or arg[4] == "false" then rept = ( arg[4] == "true" ) end play() </lang>

Output:

-------------------------------
Your guess (ABCDEF)?bcde
01: BCDE : X X - -

-------------------------------
Your guess (ABCDEF)?bcaf
01: BCDE : X X - -
02: BCAF : X O O -

-------------------------------
Your guess (ABCDEF)?badf
01: BCDE : X X - -
02: BCAF : X O O -
03: BADF : X X O -

-------------------------------
Your guess (ABCDEF)?bafe

Well done!
Play again( Y/N )?

Perl

Translation of: Raku

<lang perl>use List::Util qw(any);

print 'Enter pool size, puzzle size, attempts allowed: '; ($pool,$length,$tries) = split /\s+/, <>; $length = 4 if $length eq or $length < 3 or $length > 11; $pool = 6 if $pool eq or $pool < 2 or $pool > 21; $tries = 10 if $tries eq or $tries < 7 or $tries > 21;

@valid = sort { -1 + 2*int(rand 2) } ('A' .. 'T')[0..$pool-1]; @puzzle = @valid[0..$length-1];

$black = '●'; $white = '○';

while () {

   header();
   print "$_\n" for @guesses;
   lose() if  @guesses == $tries;
   @guess = get_guess();
   next unless is_valid(@guess);
   $score = score(\@puzzle, \@guess);
   win() if $score eq join ' ', ($black) x $length;
   push @guesses, join(' ', @guess) . ' :: ' . $score;

}

sub score {

   local *puzzle = shift;
   local *guess  = shift;
   my @score;
   for $i (0..$length-1) {
       if    (     $puzzle[$i] eq $guess[$i]) { push @score, $black }
       elsif (any {$puzzle[$i] eq $_} @guess) { push @score, $white }
       else                                   { push @score, '-'    }
   }
   join ' ', reverse sort @score;

}

sub header {

   $num = $tries - @guesses;
   print  "Valid letter, but wrong position: ○ - Correct letter and position: ●\n";
   print  "Guess the $length element sequence containing the letters " . join(', ', sort @valid) . "\n";
   printf "Repeats are not allowed. You have $num guess%s remaining\n", $num > 1 ? 'es' : ;

}

sub get_guess { print 'Your guess?: '; $g = <>; return split /\s*/, uc $g }

sub is_valid { $length == @_ }

sub win { print 'You win! The correct answer is: ' . join(' ',@puzzle) . "\n"; exit }

sub lose { print 'Too bad, you ran out of guesses. The solution was: ' . join(' ',@puzzle) . "\n"; exit } </lang> Sample output, omitting redundant instructions.

Output:

Valid letter, but wrong position: ○ - Correct letter and position: ●
Guess the 4 element sequence containing the letters A, B, C, D, E, F
Repeats are not allowed. You have 10 guesses remaining
Your guess?: a b c e
A B C E :: ○ ○ ○ -
Your guess?: b a d c
Repeats are not allowed. You have 8 guesses remaining
A B C E :: ○ ○ ○ -
B A D C :: ● ● ○ ○
Your guess?: a b c d
Repeats are not allowed. You have 7 guesses remaining
A B C E :: ○ ○ ○ -
B A D C :: ● ● ○ ○
A B C D :: ○ ○ ○ ○
Your guess?: b d a c
You win! The correct answer is: B D A C

Phix

OTT GUI solution, fully configurable with solver. <lang Phix>-- demo/rosetta/mastermind.exw constant SET_LIMIT = 1_000_000 -- above this, it uses random sampling.

constant help_text = """ The game of mastermind, with a Knuth solver.

Specify the number of colours (1..20), the code length (1..10), the number of guesses allowed (1-20), and whether colours can be repeated (auto-ticked & greyed-out inactive when length>colours).

Note that at the highest settings there are 10,240,000,000,000 possible answers: the (order n squared) analysis of that is simply not practical, as indeed is simply building the initial list of all possible answers, and therefore a fixed limit of 1,000,000 has been applied, which also just about manages to keep the program responsive. Obviously, should the actual answer not be among those samples, it cannot possibly find it, and it will tell you in plain english when that occurs. You can always trim the search space back to something more reasonable at any time, and still play the game when that limit is breached, with weaker hints.

Conversely the lowest settings do not make for an interesting game, but proved quite useful when ironing out some bugs, so were left in.

The Use button (disabled until something useful found) allows you to take the best found (so far), displayed at the top of the colours frame. Obviously "1/1 (100%)" means that it has deduced the correct answer. Below that the colours frame shows all available colours, which can be individually clicked in any order.

Press Delete or click on the last peg (in the left-hand game frame) to remove it, before the last one is placed, however once full your turn is immediately scored and cannot be undone.

New Game, Help, and Exit buttons are assumed to be self-explanatory. Changing the option settings implicitly triggers a new game, except for the number of permitted guesses, pre-game-over. Reducing the number of guesses can also be used as a means of conceding.

When a correct guess is entered or all guesses have been used the hint and colours are replaced with "GAME OVER - YOU WIN/LOSE" under the actual answer. """ include pGUI.e

Ihandle dlg, colours, codelen, maxgoes, repeats, progress,

       usehint, game_canvas, colour_canvas

integer ncolours, ncodelen, nmaxgoes bool brepeats

sequence secret = {},

        hint = {},
        guesses = {{}},
        scores = {}

-- -- note: while the game is ongoing, length(guesses) should always be -- length(scores)+1; equal lengths is equivalent to game over. --

function get_score(sequence guess, goal) integer blacks = 0, -- (right colour & place)

       whites = 0  -- ("" but wrong place)
   for i=1 to length(guess) do
       if guess[i]=goal[i] then
           blacks += 1
           guess[i] = ' '
           goal[i] = ' '
       end if
   end for
   for i=1 to length(guess) do
       if guess[i]!=' ' then
           integer k = find(guess[i],goal)
           if k then
               whites += 1
               goal[k] = ' '
           end if
       end if
   end for
   return {blacks, whites}

end function

function random_set() -- create the secret code, and/or (when rqd) a SET_LIMIT random sample

   sequence cset = tagset(ncolours),
            res = repeat(0,ncodelen)
   for i=1 to ncodelen do
       integer c = rand(length(cset))
       res[i] = cset[c]
       if not brepeats then
           cset[c..c] = {}
       end if
   end for
   return res

end function

sequence initial_set atom is_len, -- logically length(initial_set), except when > SET_LIMIT.

    excluded   -- initialset[1..excluded-1], are not, [excluded..$] are.

procedure create_initial_set()

   is_len = iff(brepeats?power(ncolours,ncodelen):k_perm(ncolours,ncodelen))
   if is_len<=SET_LIMIT then
       --
       -- generate the full set
       --
       initial_set = repeat(0,is_len)
       excluded = is_len+1 -- (ie none)
       sequence next = iff(brepeats?repeat(1,ncodelen):tagset(ncodelen))
       for i=1 to is_len do
           initial_set[i] = next
           for ndx=length(next) to 1 by -1 do
               integer n = next[ndx]
               while n<=ncolours do
                   n += 1
                   if brepeats

-- or not find(n,next[1..ndx-1]) then

                   or not find(n,next) then --(see below)
                       exit
                   end if
               end while
               next[ndx] = n
               if n<=ncolours then
                   if not brepeats then
                       --
                       -- Fill in the rest lowest-first, eg
                       -- in the 4 colours and 4 holes case:
                       --   (start)       (above)       (this)
                       --  {1,2,3,4} --> {1,2,4,_} --> {1,2,4,3}
                       --  {1,2,4,3} --> {1,3,_,_} --> {1,3,2,4}
                       --  ...   (20 other cases omitted)
                       --  {4,3,1,2} --> {4,3,2,_} --> {4,3,2,1}
                       --
                       -- (probably sub-optimal, but insignificant 
                       --  vs. the o(n^2) analysis which follows.)
                       --
                       for j=ndx+1 to length(next) do
                           for k=1 to ncolours do

-- if not find(k,next[1..j-1]) then

                               if not find(k,next) then --(see below)
                                   next[j] = k
                                   exit
                               end if
                           end for
                       end for
                   end if
                   exit
               end if
               --
               -- technical note: if not brepeats, we are going to
               -- replace all next[ndx..$] later/above anyway, but
               -- replacing with 0 means we can avoid those slices.
               -- The next three all work: 1 is perfect for the
               -- brepeats=true case, but brepeats=false needs the 
               -- above slices, while the 2nd & 3rd are equivalent
               -- the latter is obviously somewhat faster, at the
               -- cost of a wtf?!, without a comment such as this.
               --

-- next[ndx] = 1 -- next[ndx] = iff(brepeats?1:0)

               next[ndx] = brepeats -- (equivalent)
           end for
       end for
   else
       --
       -- generate SET_LIMIT random codes
       -- note that if (as is quite likely) the actual answer is
       -- not present in initial_set, then obviously it cannot
       -- possibly find it!
       --
       initial_set = repeat(0,SET_LIMIT)
       excluded = SET_LIMIT+1  -- (ie none)
       for i=1 to SET_LIMIT do
           initial_set[i] = random_set()
       end for
   end if

end procedure

atom done, is_done, best

function idle_action()

   atom to_do = excluded-1,
        t1 = time()+1
   string samp = iff(is_len=length(initial_set)?"":sprintf(" samples of %,d",{is_len}))
   for i=1 to 100000 do    -- reasonable slice of work
       done += 1
       is_done += (done<excluded)
       sequence guest = initial_set[done],
                scores = {}, counts = {}
       if not find(guest,guesses) then
           for j=1 to excluded-1 do
               sequence s = get_score(guest,initial_set[j])
               integer k = find(s,scores)
               if k=0 then
                   scores = append(scores,s)
                   counts = append(counts,1)
               else
                   counts[k] += 1
               end if
           end for
           if length(counts)=0 then
               IupSetStrAttribute(progress,"TITLE","[answer not in %,d%s]",{SET_LIMIT,samp})
               return IUP_IGNORE   -- (stop idle)
           end if
           integer k = largest(counts,return_index:=true),
                   ck = counts[k]
           if ck<best then
               best = ck
               hint = guest
               IupSetInt(usehint,"ACTIVE",true)
               IupUpdate(colour_canvas)
           end if
       end if
   
       if done=length(initial_set) then
           IupSetStrAttribute(progress,"TITLE","%,d/%,d%s (100%%)",{is_done,to_do,samp})
           return IUP_IGNORE   -- (stop idle)
       end if
       if time()>t1 then exit end if
   end for
   IupSetStrAttribute(progress,"TITLE","%,d/%,d%s (%d%%)",{is_done,to_do,samp,100*(is_done/to_do)})
   return IUP_DEFAULT

end function constant idle_action_cb = Icallback("idle_action")

procedure start_idle()

   done = 0
   is_done = 0
   best = length(initial_set)+1
   IupSetGlobalFunction("IDLE_ACTION",idle_action_cb)

end procedure

procedure new_game()

   ncolours = IupGetInt(colours,"VALUE")
   ncodelen = IupGetInt(codelen,"VALUE")
   nmaxgoes = IupGetInt(maxgoes,"VALUE")
   brepeats = IupGetInt(repeats,"VALUE")
   secret = random_set()
   guesses = {{}}
   scores = {}
   hint = {}
   create_initial_set()
   start_idle()

end procedure

constant colour_table = {#e6194b, -- Red

                        #3cb44b,   -- Green
                        #ffe119,   -- Yellow
                        #4363d8,   -- Blue
                        #f58231,   -- Orange
                        #911eb4,   -- Purple
                        #42d4f4,   -- Cyan
                        #f032e6,   -- Magenta
                        #bfef45,   -- Lime
                        #fabebe,   -- Pink
                        #469990,   -- Teal
                        #e6beff,   -- Lavender
                        #9A6324,   -- Brown
                        #fffac8,   -- Beige
                        #800000,   -- Maroon
                        #aaffc3,   -- Mint
                        #808000,   -- Olive
                        #ffd8b1,   -- Apricot
                        #000075,   -- Navy
                        #a9a9a9}   -- Grey

-- saved in redraw_cb(), for click testing in button_cb(): sequence last_guess = {},

        colour_centres = {}

integer guess_r2 = 0,

       colour_r2 = 0

function redraw_cb(Ihandle ih, integer /*posx*/, integer /*posy*/)

   Ihandle frame = IupGetParent(ih)
   string title = IupGetAttribute(ih,"TITLE")
   if not find(title,{"Game","Colours"}) then ?9/0 end if
   integer {cw,ch} = IupGetIntInt(ih, "DRAWSIZE")
   
   cdCanvas cddbuffer = IupGetAttributePtr(ih,"DBUFFER")
   IupGLMakeCurrent(ih)
   cdCanvasActivate(cddbuffer)
   cdCanvasClear(cddbuffer)

   if title="Game" then
       integer mx = min(floor(cw/(ncodelen*1.5+0.5)),floor(ch/(nmaxgoes+1))),
               diameter = floor(mx/2),
               px = floor((cw-(ncodelen*1.5+0.5)*mx)/2), -- (set margin)
               cy = ch, cx, c, r
       last_guess = {}
       for g=1 to length(guesses) do
           cy -= mx
           cx = px+floor(mx/2)
           for i=1 to 2*ncodelen+1 do
               if i!=ncodelen+1 then
                   if i<=ncodelen then
                       if i<=length(guesses[g]) then
                           c = colour_table[guesses[g][i]]
                           if g=length(guesses) then
                               last_guess = Template:Cx,ch-cy
                           end if
                       else
                           c = CD_GREY
                       end if
                       r = diameter
                   else
                       c = CD_GREY
                       if g<=length(scores) then
                           integer k = i-ncodelen-1,
                                   {b,w} = scores[g]
                           c = iff(k<=b ? CD_BLACK : iff(k<=b+w ? CD_WHITE : CD_GREY))
                       end if
                       r = floor(diameter*0.5)
                   end if
                   cdCanvasSetForeground(cddbuffer,c)
                   cdCanvasSector(cddbuffer, cx, cy, r, r, 0, 360)
                   cdCanvasSetForeground(cddbuffer,CD_DARK_GREY)
                   cdCanvasCircle(cddbuffer, cx, cy, r)
               end if
               cx += iff(i<ncodelen?mx:floor(mx/2))
           end for
       end for
       guess_r2 = floor(diameter*diameter/4)
   elsif title="Colours" then
       integer mx = min(floor(cw/ncodelen),floor(ch/2)),
               r = floor(mx/2),
               px = floor((cw-ncodelen*mx)/2), -- (set margin)
               cy = ch-r, cx, c
       cx = px+floor(mx/2)
       bool active = length(hint)>0
       if length(scores)=nmaxgoes then
           hint = secret
           active = true
       end if
       for i=1 to ncodelen do
           c = iff(active?colour_table[hint[i]]:CD_GREY)
           cdCanvasSetForeground(cddbuffer,c)
           cdCanvasSector(cddbuffer, cx, cy, r, r, 0, 360)
           cdCanvasSetForeground(cddbuffer,CD_DARK_GREY)
           cdCanvasCircle(cddbuffer, cx, cy, r)
           cx += mx
       end for
       if length(scores)=nmaxgoes
       or guesses[$]=secret then
           ch -= floor(mx/2)
           {} = cdCanvasTextAlignment(cddbuffer, CD_CENTER)
           string wl = iff(guesses[$]=secret?"WIN":"LOSE"),
                  msg = sprintf("GAME OVER - YOU %s",{wl})
           cdCanvasText(cddbuffer, cw/2, ch/2, msg) 
       else
           integer ch0 = ch
           ch -= mx
           --
           -- calculate the best nw*nh way to fit all the colours in:
           -- (if nw ends up = ncodelen there is no clear separation
           --  between the hint and the colour table; the start with
           --  ncodelen+1 solves that and looks pretty good to me.)
           --
           integer nw = ncodelen+1,    -- (as above)
                   nh = 1
           while nw*nh<ncolours do
               if (cw/(nw+1))>(ch/(nh+1)) then
                   nw += 1
               else
                   nh += 1
               end if
           end while
           --
           -- now draw all the colours
           --
           mx = min(floor(cw/nw),floor(ch/nh))
           r = floor(mx/2)
           px = floor((cw-nw*mx)/2)
           cx = px+floor(mx/2)
           cy = ch-r
           integer this_row = 0
           colour_centres = repeat(0,ncolours)
           colour_r2 = floor(r*r/4)
           for i=1 to ncolours do
               colour_centres[i] = {cx,ch0-cy}
               c = colour_table[i]
               cdCanvasSetForeground(cddbuffer,c)
               cdCanvasSector(cddbuffer, cx, cy, r, r, 0, 360)
               cdCanvasSetForeground(cddbuffer,CD_DARK_GREY)
               cdCanvasCircle(cddbuffer, cx, cy, r)
               cx += mx
               this_row += 1
               if this_row>=nw then
                   this_row = 0
                   cx = px + floor(mx/2)
                   cy -= mx
               end if
           end for
       end if
   end if
   cdCanvasFlush(cddbuffer)
   return IUP_DEFAULT

end function

function map_cb(Ihandle ih)

   IupGLMakeCurrent(ih)
   atom res = IupGetDouble(NULL, "SCREENDPI")/25.4
   cdCanvas cddbuffer = cdCreateCanvas(CD_GL, "10x10 %g", {res})
   IupSetAttributePtr(ih,"DBUFFER",cddbuffer)
   cdCanvasSetBackground(cddbuffer, CD_PARCHMENT)
   return IUP_DEFAULT

end function

function canvas_resize_cb(Ihandle canvas)

   cdCanvas cddbuffer = IupGetAttributePtr(canvas,"DBUFFER")
   integer {canvas_width, canvas_height} = IupGetIntInt(canvas, "DRAWSIZE")
   atom res = IupGetDouble(NULL, "SCREENDPI")/25.4
   cdCanvasSetAttribute(cddbuffer, "SIZE", "%dx%d %g", {canvas_width, canvas_height, res})
   return IUP_DEFAULT

end function

procedure redraw_all()

   IupUpdate({game_canvas,colour_canvas})

end procedure

procedure undo_move() -- Called from button_cb and from K_DEL, but latter may be invalid.

   if length(guesses[$])!=0 then
       guesses[$] = guesses[$][1..$-1]
       redraw_all()
   end if

end procedure

procedure add_move(integer i)

   if i!=0 then
       guesses[$] &= i
   end if
   if length(guesses[$])=ncodelen then
       sequence guest = guesses[$],
                score = get_score(guest,secret)
       scores = append(scores,score)   
       if score!={ncodelen,0}  -- (not all black==game over)
       and length(guesses)<nmaxgoes then
           for i=excluded-1 to 1 by -1 do
               sequence isi = initial_set[i]
               if get_score(guest,isi)!=score then
                   excluded -= 1
                   if excluded!=i then
                       initial_set[i] = initial_set[excluded]
                       initial_set[excluded] = isi -- (swap)
                   end if
               end if
           end for
           guesses = append(guesses,{})
           hint = {}
           IupSetAttribute(progress,"TITLE","-")
           IupSetInt(usehint,"ACTIVE",false)
           start_idle()
       end if
   end if
   redraw_all()

end procedure

function usehint_cb(Ihandle /*usehint*/)

   guesses[$] = hint
   add_move(0)
   return IUP_DEFAULT

end function

function button_cb(Ihandle canvas, integer button, pressed, x, y, atom /*pStatus*/)

   Ihandle frame = IupGetParent(canvas)
   string title = IupGetAttribute(frame,"TITLE")
   if not find(title,{"Game","Colours"}) then ?9/0 end if
   if button=IUP_BUTTON1 and not pressed then      -- (left button released)
       {sequence centres, integer r2} = iff(title="Game"?{last_guess,guess_r2}
                                                        :{colour_centres,colour_r2})
       for i=1 to length(centres) do
           integer {cx,cy} = sq_sub(centres[i],{x,y})
           if (cx*cx+cy*cy)<=r2 then
               if title="Game" then
                   undo_move()
               else
                   add_move(i)
               end if
               exit
           end if
       end for
   end if
   return IUP_CONTINUE

end function

function new_game_cb(Ihandle /*ih*/)

   new_game()
   redraw_all()
   return IUP_DEFAULT

end function

function exit_cb(Ihandle /*ih*/)

   return IUP_CLOSE

end function constant cb_exit = Icallback("exit_cb")

function help_cb(Ihandln /*ih*/)

   IupMessage("Mastermind",help_text)
   return IUP_DEFAULT

end function

function key_cb(Ihandle /*dlg*/, atom c)

   if c=K_ESC then return IUP_CLOSE end if
   if c=K_F1 then return help_cb(NULL) end if
   if find(c,{K_DEL,K_BS}) then undo_move() end if
   return IUP_CONTINUE

end function

function valuechanged_cb(Ihandle ih)

   ncolours = IupGetInt(colours,"VALUE")
   ncodelen = IupGetInt(codelen,"VALUE")
   nmaxgoes = IupGetInt(maxgoes,"VALUE")
   IupSetInt(repeats,"ACTIVE",ncodelen<=ncolours)
   if ncodelen>ncolours then
       IupSetInt(repeats,"VALUE",true)
   end if
   brepeats = IupGetInt(repeats,"VALUE")
   if ih!=maxgoes
   or length(scores)=length(guesses) then  -- (game over)
       new_game()
   elsif nmaxgoes<=length(scores) then
       -- (signal/force game over state)
       guesses = guesses[1..length(scores)]
   end if
   redraw_all()
   return IUP_DEFAULT

end function constant cb_valuechanged = Icallback("valuechanged_cb")

procedure main()

   IupOpen()

   colours = IupText("SPIN=Yes, SPINMIN=1, SPINMAX=20, VALUE=6, RASTERSIZE=34x")
   codelen = IupText("SPIN=Yes, SPINMIN=1, SPINMAX=10, VALUE=4, RASTERSIZE=34x")
   maxgoes = IupText("SPIN=Yes, SPINMIN=1, SPINMAX=20, VALUE=7, RASTERSIZE=34x")
   repeats = IupToggle("Repeatable?","VALUE=YES, RIGHTBUTTON=YES, PADDING=5x4")
   progress = IupLabel("-","EXPAND=HORIZONTAL, PADDING=5x4")
   usehint = IupButton("Use",Icallback("usehint_cb"),"PADDING=5x4, ACTIVE=NO")
   game_canvas = IupGLCanvas("RASTERSIZE=200x")
   colour_canvas = IupGLCanvas("RASTERSIZE=x200")
   Ihandle newgame = IupButton("New Game",Icallback("new_game_cb"),"PADDING=5x4"),
           help = IupButton("Help (F1)",Icallback("help_cb"),"PADDING=5x4"),
           quit = IupButton("E&xit",Icallback("exit_cb"),"PADDING=5x4"),
           vbox = IupVbox({IupHbox({IupLabel("Colours (1-20)","PADDING=5x4"),colours}),
                           IupHbox({IupLabel("Code Length (1-10)","PADDING=5x4"),codelen}),
                           IupHbox({IupLabel("Guesses (1-20)","PADDING=5x4"),maxgoes}),
                           IupHbox({repeats},"MARGIN=10x5"),
                           IupHbox({progress}),
                           IupHbox({usehint,newgame,help,quit})},"MARGIN=5x5"),
           game_frame = IupFrame(IupHbox({game_canvas},"MARGIN=3x3"),"TITLE=Game"),
           option_frame = IupFrame(vbox,"TITLE=Options"),
           colour_frame = IupFrame(colour_canvas,"TITLE=Colours"),
           full = IupHbox({game_frame,IupVbox({option_frame,colour_frame})})
   IupSetCallbacks({colours,codelen,maxgoes,repeats}, {"VALUECHANGED_CB", cb_valuechanged})
   IupSetCallbacks({game_canvas,colour_canvas}, {"ACTION", Icallback("redraw_cb"),
                                                 "MAP_CB", Icallback("map_cb"),
                                                 "RESIZE_CB", Icallback("canvas_resize_cb"),
                                                 "BUTTON_CB", Icallback("button_cb")})
   dlg = IupDialog(IupHbox({full},"MARGIN=3x3"),"TITLE=Mastermind")
   IupSetCallback(dlg, "K_ANY", Icallback("key_cb"))
   IupSetAttributeHandle(dlg,"DEFAULTENTER", usehint)

   new_game()

   IupShowXY(dlg,IUP_CENTER,IUP_CENTER)
   IupSetAttribute(dlg, "RASTERSIZE", NULL)
   IupSetStrAttribute(dlg, "MINSIZE", IupGetAttribute(dlg,"RASTERSIZE"))
   IupMainLoop()
   IupClose()

end procedure main()</lang>

Prolog

<lang Prolog>mastermind :- mastermind(7, 4, 8, no_duplicates).

mastermind(Colours, Length, Guesses, Duplicates) :- between(2, 20, Colours), between(4, 10, Length), between(7, 20, Guesses), member(Duplicates, [allow_duplicates, no_duplicates]),

create_board(Colours, Length, Duplicates, Board), intro(Colours, Length, Duplicates), play(board(Board, Length, Colours, Guesses), [], 0), !.

intro(Colours, Length, Duplicates) :- format('Guess the code!~n'), format('There are ~p character types, and ~p letters to guess~n', [Colours, Length]), Duplicates = allow_duplicates -> format('Duplicates are allowed~n~n') ; format('Duplicates are not allowed~n~n').

/* Create the combination to be guessed */ create_board(Colours, Length, Duplicates, Board) :- length(Board, Length), valid_char_list(Colours, CharSet), repeat, maplist(random_alpha(CharSet), Board), check_for_duplicates(Board, Duplicates).

check_for_duplicates(_, allow_dupicates). check_for_duplicates(Board, no_duplicates) :- is_set(Board).

/* Main loop - get the player guess and print out status */ play(board(Board,_,_,MaxGuesses), _, MaxGuesses) :- write('Sorry, You failed to guess in time...!\nThe code was : '), maplist(write, Board), nl. play(BoardData, PrevGuesses, GuessNum) :- BoardData = board(_, Length, Colours, MaxGuesses), GuessNum < MaxGuesses, ReportedGuess is GuessNum + 1, format('Guess #~p of #~p: ', [ReportedGuess, MaxGuesses]), get_player_guess(Length, Colours, Guess), evaluate_and_print_result(BoardData, PrevGuesses, ReportedGuess, Guess).

evaluate_and_print_result(board(Board,_,_,_), _, _,Board) :- format('Well done! You Guessed Correctly.~n'). evaluate_and_print_result(BoardData, PrevGuesses, NextGuessNum, Guess) :- BoardData = board(Board, _, _, _), dif(Board, Guess), match_guess_to_board(Board, Guess, Diffs), append(PrevGuesses, [guess(NextGuessNum, Guess, Diffs)], Guesses), maplist(print_guess, Guesses), play(BoardData, Guesses, NextGuessNum).

/* Get the player guess and validate that it matches the rules */ get_player_guess(Length, Colours, Guess) :- repeat, read_line_to_string(user_input, Line), string_chars(Line, Guess),

% validate the correct number of items have been entered length(Guess, Length),

% validate that all the characters are valid for the number of colours valid_char_list(Colours, ValidCharSet), subset(Guess, ValidCharSet).

/* Predicates to figure out how many places are correct */ match_guess_to_board(Board, Guess, Matches) :- maplist(guess_differences(Board), Board, Guess, Differences), sort(0, @>=, Differences, Matches).

% Same position, same type guess_differences(_Board, B, B, 'X'). % Same type, different position guess_differences(Board, B, G, 'O') :- dif(B, G), member(G, Board). % Type not on board guess_differences(Board, B, G, '-') :- dif(B, G), \+ member(G, Board).

/* Print out the current progress */ print_guess(guess(NextGuessNumber, Guess, Differences)) :- format('~w: ', NextGuessNumber), maplist(format('~w '), Guess), format(' : '), maplist(format('~w '), Differences), nl.

/* Utils */ alpha_chars([a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t]).

valid_char_list(Colours, CharSet) :- alpha_chars(AllChars), truncate_list(AllChars, Colours, CharSet).

random_alpha(AllChars, RandomMember) :- random_member(RandomMember, AllChars).

truncate_list(_, 0, []). truncate_list([A|T], N, [A|R]) :- N > 0, N1 is N - 1, truncate_list(T, N1, R).</lang>

Output:

1 ?- mastermind.
Guess the code!
There are 7 character types, and 4 letters to guess
Duplicates are not allowed

Guess #1 of #8: abcd
1: a b c d  : X O O -
Guess #2 of #8: acbe
1: a b c d  : X O O -
2: a c b e  : X O - -
Guess #3 of #8: fgab
1: a b c d  : X O O -
2: a c b e  : X O - -
3: f g a b  : O O - -
Guess #4 of #8: cdfg
1: a b c d  : X O O -
2: a c b e  : X O - -
3: f g a b  : O O - -
4: c d f g  : X X O -
Guess #5 of #8: cdfb
1: a b c d  : X O O -
2: a c b e  : X O - -
3: f g a b  : O O - -
4: c d f g  : X X O -
5: c d f b  : X X O -
Guess #6 of #8: cdaf
1: a b c d  : X O O -
2: a c b e  : X O - -
3: f g a b  : O O - -
4: c d f g  : X X O -
5: c d f b  : X X O -
6: c d a f  : X O O O
Guess #7 of #8: acdf
1: a b c d  : X O O -
2: a c b e  : X O - -
3: f g a b  : O O - -
4: c d f g  : X X O -
5: c d f b  : X X O -
6: c d a f  : X O O O
7: a c d f  : X O O O
Guess #8 of #8: adfc
Well done! You Guess Correctly.
true.

Python

Works with: cpython version 3.7.3

Tested in Python 3.7.3. Includes input verification. <lang python> import random

def encode(correct, guess):

   output_arr = [] * len(correct)

   for i, (correct_char, guess_char) in enumerate(zip(correct, guess)):
       output_arr[i] = 'X' if guess_char == correct_char else 'O' if guess_char in correct else '-'

   return .join(output_arr)

def safe_int_input(prompt, min_val, max_val):

   while True:
       user_input = input(prompt)

       try:
           user_input = int(user_input)
       except ValueError:
           continue

       if min_val <= user_input <= max_val:
           return user_input

def play_game():

   print("Welcome to Mastermind.")
   print("You will need to guess a random code.")
   print("For each guess, you will receive a hint.")
   print("In this hint, X denotes a correct letter, and O a letter in the original string but in a different position.")
   print()

   number_of_letters = safe_int_input("Select a number of possible letters for the code (2-20): ", 2, 20)
   code_length = safe_int_input("Select a length for the code (4-10): ", 4, 10)

   letters = 'ABCDEFGHIJKLMNOPQRST'[:number_of_letters]
   code = .join(random.choices(letters, k=code_length))
   guesses = []

   while True:
       print()
       guess = input(f"Enter a guess of length {code_length} ({letters}): ").upper().strip()

       if len(guess) != code_length or any([char not in letters for char in guess]):
           continue
       elif guess == code:
           print(f"\nYour guess {guess} was correct!")
           break
       else:
           guesses.append(f"{len(guesses)+1}: {' '.join(guess)} => {' '.join(encode(code, guess))}")

       for i_guess in guesses:
           print("------------------------------------")
           print(i_guess)
       print("------------------------------------")

if __name__ == '__main__':

   play_game()

</lang>

Output:

Welcome to Mastermind.
You will need to guess a random code.
For each guess, you will receive a hint.
In this hint, X denotes a correct letter, and O a letter in the original string but a different position.

Select a number of possible letters for the code (2-20): 4
Select a length for the code (4-10): 4

*omitted first guesses*

Enter a guess of length 4 (ABCD): cdaa
------------------------------------
1: A A B B => O O - -
------------------------------------
2: C D A A => O X X O
------------------------------------

Enter a guess of length 4 (ABCD): ddac

Your guess DDAC was correct!

Raku

(formerly Perl 6)

Works with: Rakudo version 2017.01

By default, plays classic Mastermind using letters in place of colors. ( 4 chosen from 6, no repeats, 10 guess limit. ) Pass in parameters to modify the game. Enter a string of --length (default 4) letters with or without spaces. Guesses accept lower or upper case. <lang perl6>sub MAIN (

   Int :$colors  where 1 < * < 21 = 6,  Int :$length  where 3 < * < 11 = 4,
   Int :$guesses where 7 < * < 21 = 10, Bool :$repeat = False
 ) {
   my @valid = ('A' .. 'T')[^$colors];
   my $puzzle = $repeat ?? @valid.roll($length) !! @valid.pick($length);
   my @guesses;

   my $black = '●';
   my $white = '○';

   loop {
       clearscr();
       say header();
       printf " %{$length * 2}s :: %s\n", @guesses[$_][0], @guesses[$_][1] for ^@guesses;
       say ;
       lose() if @guesses == $guesses;
       my $guess = get-guess();
       next unless $guess.&is-valid;
       my $score = score($puzzle, $guess);
       win() if $score eq ($black xx $length).join: ' ';
       @guesses.push: [$guess, $score];
   }

   sub header {
       my $num = $guesses - @guesses;
       qq:to/END/;
       Valid letter, but wrong position: ○ - Correct letter and position: ●
       Guess the {$length} element sequence containing the letters {@valid}
       Repeats are {$repeat ??  !! 'not '}allowed. You have $num guess{ $num == 1 ??  !! 'es'} remaining.
       END
   }

   sub score ($puzzle, $guess) {
       my @score;
       for ^$length {
           if $puzzle[$_] eq $guess[$_] {
               @score.push: $black;
           }
           elsif $puzzle[$_] eq any(@$guess) {
               @score.push: $white;
           }
           else {
               @score.push('-');
           }
       }
       @score.sort.reverse.join: ' ';
   }

   sub clearscr { $*KERNEL ~~ /'win32'/ ?? run('cls') !! run('clear') }

   sub get-guess { (uc prompt 'Your guess?: ').comb(/@valid/) }

   sub is-valid (@guess) { so $length == @guess }

   sub win  { say 'You Win! The correct answer is: ', $puzzle; exit }

   sub lose { say 'Too bad, you ran out of guesses. The solution was: ', $puzzle; exit }

}</lang>

Sample output:

Valid letter, but wrong position: ○ - Correct letter and position: ●
Guess the 4 element sequence containing the letters A B C D E F
Repeats are not allowed. You have 5 guesses remaining.

  A B C D :: ○ ○ ○ -
  C A B E :: ● ○ ○ -
  D A E F :: ● ○ - -
  B A E C :: ● ○ ○ -
  D E B C :: ○ ○ ○ ○

Your guess?: cdeb
You Win! The correct answer is: (C D E B)

REXX

More checks could have been added (for illegal inputs and illegal options). <lang rexx>/*REXX pgm scores mastermind game with a human or CBLFs (Carbon Based Life Forms). */ parse arg let wid mxG oRep seed _ /*obtain optional arguments from the CL*/

     arg  .   .   .   rep .                     /*get uppercase 4th argument  "   "  " */

if let== | let=="," then let= 20 /*Not specified? Then use the default.*/ if wid== | wid=="," then wid= 4 /* " " " " " " */ if mxG== | mxG=="," then mxG= 20 /* " " " " " " */ if rep== | rep=="," then rep= 0 /* " " " " " " */ if datatype(seed,'W') then call random ,,seed /*use a seed for random repeatability. */ if abbrev( 'REPEATSALLOWED',rep,3) then rep=1 /*allow an abbreviated option for REP. */ if abbrev('NOREPEATSALLOWED',rep,3) then rep=0 /* " " " " " " */ call vet arg(), 'args' /*Vet the number of arguments entered. */ /*◄■■■■■■ optional vetting.*/ call vet let, 'letters', 2, 20 /* " " " " letters in the code*/ /*◄■■■■■■ optional vetting.*/ call vet wid, 'width', 4, 10 /* " " " " the width of code. */ /*◄■■■■■■ optional vetting.*/ call vet mxG, 'maxGuess', 7, 20 /* " " " " maximum guesses. */ /*◄■■■■■■ optional vetting.*/ call vet rep, 'REP', 0, 1e8 /* " " value if repeats are allowed*/ /*◄■■■■■■ optional vetting.*/ call gen; yourG= 'Your guess must be exactly '

                                                youve= "You've already tried that guess "
       do prompt=0  by 0  until xx==wid;   say  /*play until guessed or QUIT is entered*/
       say id 'Please enter a guess with '   wid  ' letters                   [or Quit]:'
       pull g;   g=space(g,0);  L=length(g);     if abbrev('QUIT',g,1)  then exit 0
       if L\==wid  then do;  say id '***error***'  yourG wid  " letters.";  iterate;  end
       call dups                                /*look through the history log for dups*/
       q=?;      XX=0;      OO=0;     try=try+1 /*initialize some REXX vars;  bump TRY.*/

            do j=1  for L;  if substr(g,j,1) \== substr(q,j,1)  then iterate    /*hit? */
            xx=xx+1;    q=overlay('▒', q, j)    /*bump the  XX  correct   count.       */
            end   /*j*/                         /* [↑]  XX  correct count; scrub guess.*/

            do k=1  for L;   _=substr(g, k, 1)  /*process the count for  "spots".      */
            if pos(_, q)==0  then iterate       /*is this  (spot)  letter in the code? */
            oo=oo+1;       q=translate(q, , _)  /*bump the  OO  spot count.            */
            end   /*k*/                         /* [↑]  OO  spot count;  & scrub guess.*/
       say
       @.try=id  right('guess'  try, 11)     '  ('mxG       "is the max):"    g   '──►' ,
                                     copies('X', xx)copies("O", oo)copies('-', wid-xx-oo)
       call hist
       if try==mxG  then do;  say;      say id   "you've used the maximum guesses:"   mxG
                              say;      say id   "The code was: "   ?;    say;     exit 1
                         end
       end   /*prompt*/

say; say " ┌─────────────────────────────────────────┐"

                              say "          │                                         │"
                              say "          │  Congratulations, you've guessed it !!  │"
                              say "          │                                         │"
                              say "          └─────────────────────────────────────────┘"

exit 0 /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ dups: do h=1 for try; if g\=word(@.h, 8) then iterate /*any duplicated guesses? */

        say;  say id youve  " (guess number" h').'; iterate prompt; end  /*h*/;    return

/*──────────────────────────────────────────────────────────────────────────────────────*/ gen: if rep==0 then reps= 'no' /*create a literal for the prompt msg. */

                else reps=
     @abc= 'QWERTYUIOPASDFGHJKLZXCVBNM'         /*capital letters used for random code.*/
     id='────────';  try=0;  L@abc=length(@abc) /*identifier in front of msg from here.*/
     ?=
         do  until  length(?)==wid              /*gen random codes 'til there's enough.*/
         r=substr(@abc, random(1, L@abc), 1)    /*generate a random letter, 1 at a time*/
         if \rep & pos(r, ?)\==0  then iterate  /*maybe  don't  allow a repeated digit.*/
         ?=? || r; if ?=='QUIT'&let==4  then ?= /*append random letter; ··· except this*/
         end   /*until*/                        /* [↑]  builds a unique  N-letter code.*/
     say
     say id 'A random code of '   wid   "letters  (out of a possible "  let  ' letters) '
     say id 'has been generated   (with'    reps    "repeats)."
     return

/*──────────────────────────────────────────────────────────────────────────────────────*/ hist: do hist=1 for try; say @.hist; end; return /*show "guess" history.*/ s: if arg(1)==1 then return ; return "s" /*a simpler pluraizer. */ ser: say; say; say '***error***' arg(1); say; say; exit 13 /*──────────────────────────────────────────────────────────────────────────────────────*/ /*◄■■■■■■ optional vetting.*/ vet: parse arg val,?,mn,mx /*vet (validate) a specified argument. */ /*◄■■■■■■ optional vetting.*/

     if ?=="args" & (val>1 | _\=)  then call ser "Too many arguments specified. "  _     /*◄■■■■■■ optional vetting.*/
     if ?=="args"       then return                                                        /*◄■■■■■■ optional vetting.*/
     if \datatype(val, 'N')          then call ser ? "isn't numeric: "               val   /*◄■■■■■■ optional vetting.*/
     if \datatype(val, 'W')          then call ser ? "isn't an integer: "            val   /*◄■■■■■■ optional vetting.*/
     if val < mn                     then call ser ? "has a value less than "        mn    /*◄■■■■■■ optional vetting.*/
     if val > mx                     then call ser ? "has a value greater than "     mx    /*◄■■■■■■ optional vetting.*/
     if ?=='REP' & \datatype(val,W)  then call ser "Value for REPEATS isn't valid: " oRep  /*◄■■■■■■ optional vetting.*/
     return 1</lang>

output

──────── A random code of  4 letters  (out of a possible  20  letters)
──────── has been generated   (with no repeats).

──────── Please enter a guess with  4  letters                   [or Quit]:
abcd                  ◄■■■■■■ user input

────────     guess 1   (20 is the max): ABCD ──► ----

──────── Please enter a guess with  4  letters                   [or Quit]:
efgh                  ◄■■■■■■ user input

────────     guess 1   (20 is the max): ABCD ──► ----
────────     guess 2   (20 is the max): EFGH ──► ----

──────── Please enter a guess with  4  letters                   [or Quit]:
ijkl                  ◄■■■■■■ user input

────────     guess 1   (20 is the max): ABCD ──► ----
────────     guess 2   (20 is the max): EFGH ──► ----
────────     guess 3   (20 is the max): IJKL ──► O---

──────── Please enter a guess with  4  letters                   [or Quit]:
mnop                  ◄■■■■■■ user input

     ···············································
     ·    (Some of the output has been elided.)    ·
     ···············································

──────── Please enter a guess with  4  letters                   [or Quit]:
yinp                  ◄■■■■■■ user input

────────     guess 1   (20 is the max): ABCD ──► ----
────────     guess 2   (20 is the max): EFGH ──► ----
────────     guess 3   (20 is the max): IJKL ──► O---
────────     guess 4   (20 is the max): MNOP ──► XO--
────────     guess 5   (20 is the max): WXYZ ──► O---
────────     guess 6   (20 is the max): LKHI ──► O---
────────     guess 7   (20 is the max): PONM ──► XO--
────────     guess 8   (20 is the max): ZYXW ──► O---
────────     guess 9   (20 is the max): YZWX ──► X---
────────    guess 10   (20 is the max): MOPN ──► OO--
────────    guess 11   (20 is the max): OMPN ──► OO--
────────    guess 12   (20 is the max): LKJI ──► O---
────────    guess 13   (20 is the max): JILK ──► X---
────────    guess 14   (20 is the max): YINP ──► XXXX

          ┌─────────────────────────────────────────┐
          │                                         │
          │  Congratulations, you've guessed it !!  │
          │                                         │
          └─────────────────────────────────────────┘

Ring

Project : Mastermind

colors = ["A", "B", "C", "D"] places = list(2) mind = list(len(colors)) rands = list(len(colors)) master = list(len(colors)) test = list(len(colors)) guesses = 7 repeat = false nr = 0

if repeat

  for n = 1 to len(colors)
       while true
                 rnd = random(len(colors)-1) + 1
                 if rands[rnd] != 1
                    mind[n] = rnd
                    rands[rnd] = 1
                   exit
                 ok
       end     
  next

else

  for n = 1 to len(colors)
       rnd = random(len(colors)-1) + 1
       mind[n] = rnd
   next

ok

for n = 1 to len(colors)

     master[n] = char(64+mind[n])

next while true

        for p = 1 to len(places)
              places[p] = 0
        next
        nr = nr + 1
        see "Your guess (ABCD)? "
        give testbegin
        for d = 1 to len(test)
              test[d] = testbegin[d]
        next 
        flag = 1
        for n = 1 to len(test)
              if upper(test[n]) != master[n]
                 flag = 0
              ok
        next
        if flag = 1
           exit
        else
           for x = 1 to len(master)
                 if upper(test[x]) = master[x]
                     places[1] = places[1] + 1
                 ok                  
           next
           mastertemp = master
           for p = 1 to len(test)
                 pos = find(mastertemp, upper(test[p]))
                 if pos > 0 
                    del(mastertemp, pos)
                    places[2] = places[2] + 1
                 ok
           next 
        ok
        place1 = places[1] 
        place2 = places[2] - place1
        place3 = len(master) - (place1 + place2)
        showresult(test, place1, place2, place3)
        if nr = guesses
           exit
        ok

end see "Well done!" + nl see "End of game" + nl

func showresult(test, place1, place2, place3)

       see "" + nr + " : " 
       for r = 1 to len(test)
            see test[r]
       next
       see " : "
       for n1 = 1 to place1
             see "X" + " "
       next
       for n2 = 1 to place2
             see "O" + " "
       next
       for n3 = 1 to place3
             see "-" + " "
       next
       see nl

</lang> Output:

Your guess (ABCD)? BCDA
1 : BCDA : X X O - 
Your guess (ABCD)? BCDB
2 : BCDB : X X X - 
Your guess (ABCD)? BCBB
3 : BCBB : X X X - 
Your guess (ABCD)? BCAB
Well done!
End of game

Rust

Library: rand

<lang rust>extern crate rand;

use rand::prelude::*; use std::io;

fn main() {

   let mut input_line = String::new();
   let colors_n;
   let code_len;
   let guesses_max;
   let colors_dup;

   loop {
       println!("Please enter the number of colors to be used in the game (2 - 20): ");
       input_line.clear();
       io::stdin()
           .read_line(&mut input_line)
           .expect("The read line failed.");
       match (input_line.trim()).parse::<i32>() {
           Ok(n) => {
               if n >= 2 && n <= 20 {
                   colors_n = n;
                   break;
               } else {
                   println!("Outside of range (2 - 20).");
               }
           }
           Err(_) => println!("Invalid input."),
       }
   }
   let colors = &"ABCDEFGHIJKLMNOPQRST"[..colors_n as usize];

   println!("Playing with colors {}.\n", colors);

   loop {
       println!("Are duplicated colors allowed in the code? (Y/N): ");
       input_line.clear();
       io::stdin()
           .read_line(&mut input_line)
           .expect("The read line failed.");
       if ["Y", "N"].contains(&&input_line.trim().to_uppercase()[..]) {
           colors_dup = input_line.trim().to_uppercase() == "Y";
           break;
       } else {
           println!("Invalid input.");
       }
   }
   println!(
       "Duplicated colors {}allowed.\n",
       if colors_dup { "" } else { "not " }
   );
   loop {
       let min_len = if colors_dup { 4 } else { 4.min(colors_n) };
       let max_len = if colors_dup { 10 } else { 10.min(colors_n) };
       println!(
           "Please enter the length of the code ({} - {}): ",
           min_len, max_len
       );
       input_line.clear();
       io::stdin()
           .read_line(&mut input_line)
           .expect("The read line failed.");
       match (input_line.trim()).parse::<i32>() {
           Ok(n) => {
               if n >= min_len && n <= max_len {
                   code_len = n;
                   break;
               } else {
                   println!("Outside of range ({} - {}).", min_len, max_len);
               }
           }
           Err(_) => println!("Invalid input."),
       }
   }
   println!("Code of length {}.\n", code_len);
   loop {
       println!("Please enter the number of guesses allowed (7 - 20): ");
       input_line.clear();
       io::stdin()
           .read_line(&mut input_line)
           .expect("The read line failed.");
       match (input_line.trim()).parse::<i32>() {
           Ok(n) => {
               if n >= 7 && n <= 20 {
                   guesses_max = n;
                   break;
               } else {
                   println!("Outside of range (7 - 20).");
               }
           }
           Err(_) => println!("Invalid input."),
       }
   }
   println!("{} guesses allowed.\n", guesses_max);

   let mut rng = rand::thread_rng();
   let mut code;
   if colors_dup {
       code = (0..code_len)
           .map(|_| ((65 + rng.gen_range(0, colors_n) as u8) as char))
           .collect::<Vec<_>>();
   } else {
       code = colors.chars().collect::<Vec<_>>();
       code.shuffle(&mut rng);
       code = code[..code_len as usize].to_vec();
   }
   //code = vec!['J', 'A', 'R', 'D', 'A', 'N', 'I'];
   //println!("Secret code: {:?}", code);
   let mut guesses: Vec<(String, String)> = vec![];
   let mut i = 1;
   loop {
       println!("Your guess ({}/{})?: ", i, guesses_max);
       input_line.clear();
       io::stdin()
           .read_line(&mut input_line)
           .expect("The read line failed.");
       let mut guess = input_line.trim().to_uppercase();
       if guess.len() as i32 > code_len {
           guess = guess[..code_len as usize].to_string();
       }
       let guess_v = guess.chars().collect::<Vec<char>>();
       let res = evaluate(&code, &guess_v);
       guesses.push((guess, res.clone()));
       let width = 8 + guesses_max.to_string().len() + code_len as usize * 2;
       println!("{}", "-".repeat(width));
       for (i, guess) in guesses.iter().enumerate() {
           let line = format!(
               " {:w1$} : {:w2$} : {:w2$} ",
               i + 1,
               guess.0,
               guess.1,
               w1 = guesses_max.to_string().len(),
               w2 = code_len as usize
           );
           println!("{}", line);
       }
       println!("{}", "-".repeat(width));
       if res == "X".repeat(code_len as usize) {
           println!("You won! Code: {}", code.into_iter().collect::<String>());
           break;
       }
       i += 1;
       if i > guesses_max {
           println!("You lost. Code: {}", code.into_iter().collect::<String>());
           break;
       }
   }

}

fn evaluate(code: &[char], guess: &[char]) -> String {

   let mut res: Vec<char> = vec![];
   for i in 0..guess.len() {
       if guess[i] == code[i] {
           res.push('X');
       } else if code.contains(&guess[i]) {
           res.push('O');
       } else {
           res.push('-');
       }
   }
   res.sort_by(|a, b| b.cmp(a));
   res.into_iter().collect()

}</lang>

Output:

Please enter the number of colors to be used in the game (2 - 20):
20
Playing with colors ABCDEFGHIJKLMNOPQRST.

Are duplicated colors allowed in the code? (Y/N):
n
Duplicated colors not allowed.

Please enter the length of the code (4 - 10):
10
Code of length 10.

Please enter the number of guesses allowed (7 - 20):
20
20 guesses allowed.

Your guess (1/20)?:
abcdefghi
------------------------------
  1 : ABCDEFGHI  : OOOOOO---
------------------------------
<...>
Your guess (20/20)?:
ipgecnmhdk
------------------------------
  1 : ABCDEFGHI  : OOOOOO---
  2 : ABCDE      : OOO--
  3 : ABC        : O--
  4 : DEBF       : OO--
  5 : DEAG       : OOO-
  6 : DEAH       : OOO-
  7 : DEAGH      : OOOO-
  8 : DEGHI      : XOOOO
  9 : JKLMN      : OOO--
 10 : JKL        : O--
 11 : K          : O
 12 : DEGHIK     : XOOOOO
 13 : MN         : OO
 14 : OPQ        : X--
 15 : QRS        : ---
 16 : PT         : O-
 17 : PEGHIKCMND : XOOOOOOOOO
 18 : HKMNICDPEG : OOOOOOOOOO
 19 : EGNHKMPDCI : OOOOOOOOOO
 20 : IPGECNMHDK : XXXXXXXXOO
------------------------------
You lost. Code: IPGECHMNDK

SQL

   -- Create Table
   -- Distinct combination
   --- R :Red, B :Blue, G: Green, V: Violet, O: Orange, Y: Yellow
   DROP TYPE IF EXISTS color cascade;CREATE TYPE color AS ENUM ('R', 'B', 'G', 'V', 'O', 'Y');

   DROP TABLE IF EXISTS guesses cascade ; CREATE TABLE guesses (
       first color,
       second color,
       third color ,
       fourth color
   );
   CREATE TABLE mastermind () inherits (guesses);

   INSERT INTO mastermind values ('G', 'B', 'R', 'V');

   INSERT INTO guesses values ('Y', 'Y', 'B', 'B');
   INSERT INTO guesses values ('V', 'R', 'R', 'Y');
   INSERT INTO guesses values ('G', 'V', 'G', 'Y');
   INSERT INTO guesses values ('R', 'R', 'V', 'Y');
   INSERT INTO guesses values ('B', 'R', 'G', 'V');
   INSERT INTO guesses values ('G', 'B', 'R', 'V');

   --- Matches Black
   CREATE OR REPLACE FUNCTION check_black(guesses,  mastermind) RETURNS integer AS $$
       SELECT (
           ($1.first  = $2.first)::int +
           ($1.second  = $2.second)::int +
           ($1.third = $2.third)::int +
           ($1.fourth = $2.fourth)::int
       );
   $$ LANGUAGE SQL;

   --- Matches White
   CREATE OR REPLACE FUNCTION check_white(guesses,  mastermind) RETURNS integer AS $$
       SELECT (
           case when ($1.first = $2.first) then 0 else 0 end +
           case when ($1.second = $2.second) then 0 else 0 end +
           case when ($1.third = $2.third)  then 0 else 0 end +
           case when ($1.fourth = $2.fourth) then 0 else 0 end +
           case when ($1.first != $2.first) then (
                   $1.first = $2.second or
                   $1.first = $2.third or
                   $1.first = $2.fourth
                   )::int else 0 end +
           case when ($1.second != $2.second) then (
                   $1.second = $2.first or
                   $1.second = $2.third or
                   $1.second = $2.fourth
                   )::int else 0 end +
           case when ($1.third != $2.third) then (
                   $1.third = $2.first or
                   $1.third = $2.second or
                   $1.third = $2.fourth
                   )::int else 0 end +
           case when ($1.fourth != $2.fourth) then (
                   $1.fourth = $2.first or
                   $1.fourth = $2.second or
                   $1.fourth = $2.third
                   )::int else 0 end
       ) from guesses
   $$ LANGUAGE SQL;

   SELECT guesses,
          check_black(guesses.*, mastermind.*),
          check_white(guesses.*, mastermind.*)
       FROM   guesses, mastermind

</lang>

zkl

Translation of: C++

<lang zkl>class MasterMind{

  fcn init(code_len,guess_count){
     var codeLen =code_len.max(4).min(10);
     var guessCnt=guess_count.max(7).min(20);
     var colors  ="ABCDEFGHIJKLMNOPQRST"[0,codeLen];
  }
  fcn play{
     guesses,win,blackWhite:=List(),False,Void;
     code:=codeLen.pump(String,'wrap(_){ colors[(0).random(codeLen)] });
     do(guessCnt){

str:=getInput(); win,blackWhite = checkInput(str,code); guesses.append(T(str,blackWhite)); showBoard(guesses); if(win) break;

     }
     if(win) println("--------------------------------\n",

"Very well done!\nYou found the code: ",code);

      else println("--------------------------------\n",

"I am sorry, you didn't discover the code!\nThe code was: ",code);

   }
   fcn [private] showBoard(guesses){
      foreach n,gbw in ([1..].zip(guesses)){
         guess,blackWhite := gbw;
         println("%2d: %s :% s %s".fmt(n,

guess.split("").concat(" "), blackWhite.split("").concat(" "), "- "*(codeLen - blackWhite.len())));

      }
   }
   fcn [private] getInput{
      while(True){

a:=ask("Enter your guess (" + colors + "): ").toUpper()[0,codeLen]; if(not (a-colors) and a.len()>=codeLen) return(a);

      }
   }
   fcn [private] checkInput(guess,code){

// black: guess is correct in both color and position

       // white: correct color, wrong position

matched,black := guess.split("").zipWith('==,code), matched.sum(0); // remove black from code, prepend null to make counting easy code = L("-").extend(matched.zipWith('wrap(m,peg){ m and "-" or peg },code)); white:=0; foreach m,p in (matched.zip(guess)){ if(not m and (z:=code.find(p))){ white+=1; code[z]="-"; } } return(black==codeLen,"X"*black + "O"*white)

}(4,12).play();</lang>

Output:

Enter your guess (ABCD): abcd
 1: A B C D : X O O - 
Enter your guess (ABCD): abcc
 1: A B C D : X O O - 
 2: A B C C : O O - - 
Enter your guess (ABCD): aaad
 1: A B C D : X O O - 
 2: A B C C : O O - - 
 3: A A A D : X - - - 
Enter your guess (ABCD): bccd
 1: A B C D : X O O - 
 2: A B C C : O O - - 
 3: A A A D : X - - - 
 4: B C C D : X X O - 
Enter your guess (ABCD): dcbd
 1: A B C D : X O O - 
 2: A B C C : O O - - 
 3: A A A D : X - - - 
 4: B C C D : X X O - 
 5: D C B D : X X X X 
--------------------------------
Very well done!
You found the code: DCBD