ABC words

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Revision as of 17:27, 14 November 2021 by Puppydrum64 (talk | contribs) (omit)
ABC words is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.
Definition

A word is an   ABC word   if the letters  "a",  "b"  and  "c"  appear in the word in alphabetical order.

If any or all of these letters occur more than once in a word, then only the first occurrence of each letter should be used to determine whether a word is an  ABC word  or not.


Task

Show here   (on this page)   every  ABC word  in unixdict.txt.


Other tasks related to string operations:
Metrics
Counting
Remove/replace
Anagrams/Derangements/shuffling
Find/Search/Determine
Formatting
Song lyrics/poems/Mad Libs/phrases
Tokenize
Sequences



11l

<lang 11l>L(ln) File(‘unixdict.txt’).read().split("\n")

  V? a = ln.find(‘a’)
  I a != N
     V b = ln.findi(‘b’)
     I a < b & b < ln.findi(‘c’)
        print(ln)</lang>
Output:
aback
abacus
abc
abdicate
abduct
abeyance
abject
abreact
abscess
abscissa
abscissae
absence
abstract
abstracter
abstractor
adiabatic
aerobacter
aerobic
albacore
alberich
albrecht
algebraic
alphabetic
ambiance
ambuscade
aminobenzoic
anaerobic
arabic
athabascan
auerbach
diabetic
diabolic
drawback
fabric
fabricate
flashback
halfback
iambic
lampblack
leatherback
metabolic
nabisco
paperback
parabolic
playback
prefabricate
quarterback
razorback
roadblock
sabbatical
snapback
strabismic
syllabic
tabernacle
tablecloth

Action!

In the following solution the input file is loaded from H6 drive. Altirra emulator automatically converts CR/LF character from ASCII into 155 character in ATASCII charset used by Atari 8-bit computer when one from H6-H10 hard drive under DOS 2.5 is used. <lang Action!>BYTE FUNC FindC(CHAR ARRAY text CHAR c)

 BYTE i
 i=1
 WHILE i<=text(0)
 DO
   IF text(i)=c THEN
     RETURN (i)
   FI
   i==+1
 OD

RETURN (0)

BYTE FUNC IsAbcWord(CHAR ARRAY word)

 BYTE a,b,c
 a=FindC(word,'a)
 IF a=0 THEN RETURN (0) FI
 b=FindC(word,'b)
 IF b<a THEN RETURN (0) FI
 c=FindC(word,'c)
 IF c=40 THEN
       PutE() pos=2
     FI
     Print(line) Put(32)
     pos==+line(0)+1
   FI
 OD
 Close(dev)

RETURN

PROC Main()

 CHAR ARRAY fname="H6:UNIXDICT.TXT"
 FindAbcWords(fname)

RETURN</lang>

Output:

Screenshot from Atari 8-bit computer

aback abacus abc abdicate abduct
abeyance abject abreact abscess
abscissa abscissae absence abstract
abstracter abstractor adiabatic
aerobacter aerobic albacore alberich
albrecht algebraic alphabetic
ambiance ambuscade aminobenzoic
anaerobic arabic athabascan auerbach
diabetic diabolic drawback fabric
fabricate flashback halfback iambic
lampblack leatherback metabolic
nabisco paperback parabolic playback
prefabricate quarterback razorback
roadblock sabbatical snapback
strabismic syllabic tabernacle
tablecloth

Ada

<lang Ada>with Ada.Text_Io; with Ada.Strings.Fixed;

procedure Abc_Words is

  use Ada.Text_Io;
  function Is_Abc_Word (Word : String) return Boolean is
     use Ada.Strings.Fixed;
     Pos_A : constant Natural := Index (Word, "a");
     Pos_B : constant Natural := Index (Word, "b");
     Pos_C : constant Natural := Index (Word, "c");
  begin
     return
       Pos_B > Pos_A and Pos_C > Pos_B and
       Pos_A /= 0 and Pos_B /= 0 and Pos_C /= 0;
  end Is_Abc_Word;
  Filename : constant String := "unixdict.txt";
  File     : File_Type;
  Column   : Ada.Text_Io.Count := 0;

begin

  Open (File, In_File, Filename);
  while not End_Of_File (File) loop
     declare
        Word : constant String := Get_Line (File);
     begin
        if Is_Abc_Word (Word) then
           Set_Col (1 + Column);
           Column := (Column + 15) mod 120;
           Put (Word);
        end if;
     end;
  end loop;
  Close (File);

end Abc_Words;</lang>

Output:
aback          abacus         abc            abdicate       abduct         abeyance       abject         abreact
abscess        abscissa       abscissae      absence        abstract       abstracter     abstractor     adiabatic
aerobacter     aerobic        albacore       alberich       albrecht       algebraic      alphabetic     ambiance
ambuscade      aminobenzoic   anaerobic      arabic         athabascan     auerbach       diabetic       diabolic
drawback       fabric         fabricate      flashback      halfback       iambic         lampblack      leatherback
metabolic      nabisco        paperback      parabolic      playback       prefabricate   quarterback    razorback
roadblock      sabbatical     snapback       strabismic     syllabic       tabernacle     tablecloth

ALGOL 68

<lang algol68># find words that have "a", "b" and "C" in order in them # IF FILE input file;

   STRING file name = "unixdict.txt";
   open( input file, file name, stand in channel ) /= 0

THEN

   # failed to open the file #
   print( ( "Unable to open """ + file name + """", newline ) )

ELSE

   # file opened OK #
   BOOL at eof := FALSE;
   # set the EOF handler for the file #
   on logical file end( input file, ( REF FILE f )BOOL:
                                    BEGIN
                                        # note that we reached EOF on the #
                                        # latest read #
                                        at eof := TRUE;
                                        # return TRUE so processing can continue #
                                        TRUE
                                    END
                      );
   INT abc count := 0;
   WHILE STRING word;
         get( input file, ( word, newline ) );
         NOT at eof
   DO
       IF  INT w pos := LWB word;
           INT w max  = UPB word;
           INT a pos := w max + 1;
           INT b pos := w max + 1;
           INT c pos := w max + 1;
           char in string( "a", a pos, word );
           char in string( "b", b pos, word );
           char in string( "c", c pos, word );
           a pos <  b pos
       AND b pos <  c pos
       AND c pos <= w max
       THEN
           abc count +:= 1;
           print( ( whole( abc count, -5 ), ": ", word, newline ) )
       FI
   OD;
   close( input file )

FI</lang>

Output:
    1: aback
    2: abacus
    3: abc
    4: abdicate
    5: abduct
    6: abeyance
    7: abject
    8: abreact
    9: abscess
   10: abscissa
   11: abscissae
   12: absence
   13: abstract
   14: abstracter
   15: abstractor
   16: adiabatic
   17: aerobacter
   18: aerobic
   19: albacore
   20: alberich
   21: albrecht
   22: algebraic
   23: alphabetic
   24: ambiance
   25: ambuscade
   26: aminobenzoic
   27: anaerobic
   28: arabic
   29: athabascan
   30: auerbach
   31: diabetic
   32: diabolic
   33: drawback
   34: fabric
   35: fabricate
   36: flashback
   37: halfback
   38: iambic
   39: lampblack
   40: leatherback
   41: metabolic
   42: nabisco
   43: paperback
   44: parabolic
   45: playback
   46: prefabricate
   47: quarterback
   48: razorback
   49: roadblock
   50: sabbatical
   51: snapback
   52: strabismic
   53: syllabic
   54: tabernacle
   55: tablecloth

APL

Works with: Dyalog APL

<lang apl>abcwords←{

   ⍺←'abc'
   words←((~∊)∘⎕TC⊆⊢) 80 ¯1⎕MAP ⍵
   match←∧/∊,2</⍳⍨
   (⍺∘match¨words)/words

}</lang>

Output:
      11 5 ⍴ abcwords 'unixdict.txt'
 aback         abacus       abc         abdicate    abduct      
 abeyance      abject       abreact     abscess     abscissa    
 abscissae     absence      abstract    abstracter  abstractor  
 adiabatic     aerobacter   aerobic     albacore    alberich    
 albrecht      algebraic    alphabetic  ambiance    ambuscade   
 aminobenzoic  anaerobic    arabic      athabascan  auerbach    
 diabetic      diabolic     drawback    fabric      fabricate   
 flashback     halfback     iambic      lampblack   leatherback 
 metabolic     nabisco      paperback   parabolic   playback    
 prefabricate  quarterback  razorback   roadblock   sabbatical  
 snapback      strabismic   syllabic    tabernacle  tablecloth  

Arturo

<lang rebol>words: read.lines relative "unixdict.txt"

isABC?: function [w][

   a: index w "a"
   if null? a -> return false
   b: index w "b"
   if null? b -> return false
   if b < a -> return false
   c: index w "c"
   if null? c -> return false
   if c < b -> return false
   return true 

]

loop words 'word [

   if isABC? word ->
       print word

]</lang>

Output:
aback
abacus
abc
abdicate
abduct
abeyance
abject
abreact
abscess
abscissa
abscissae
absence
abstract
abstracter
abstractor
adiabatic
aerobacter
aerobic
albacore
alberich
albrecht
algebraic
alphabetic
ambiance
ambuscade
aminobenzoic
anaerobic
arabic
athabascan
auerbach
diabetic
diabolic
drawback
fabric
fabricate
flashback
halfback
iambic
lampblack
leatherback
metabolic
nabisco
paperback
parabolic
playback
prefabricate
quarterback
razorback
roadblock
sabbatical
snapback
strabismic
syllabic
tabernacle
tablecloth

AutoHotkey

<lang autohotkey>FileRead, unixdict, unixdict.txt Loop, Parse, unixdict, `n if ABCWord(A_LoopField) { count++ text .= count ": " A_LoopField "`n" } Msgbox, %text%

ABCWord(Word) { if InStr(Word, "a") if InStr(Word, "b") > InStr(Word, "a") if InStr(Word, "c") > InStr(Word, "b") return true else return false else return false else return false } </lang>

Output:
1: aback
2: abacus
3: abc
4: abdicate
5: abduct
6: abeyance
7: abject
8: abreact
9: abscess
10: abscissa
11: abscissae
12: absence
13: abstract
14: abstracter
15: abstractor
16: adiabatic
17: aerobacter
18: aerobic
19: albacore
20: alberich
21: albrecht
22: algebraic
23: alphabetic
24: ambiance
25: ambuscade
26: aminobenzoic
27: anaerobic
28: arabic
29: athabascan
30: auerbach
31: diabetic
32: diabolic
33: drawback
34: fabric
35: fabricate
36: flashback
37: halfback
38: iambic
39: lampblack
40: leatherback
41: metabolic
42: nabisco
43: paperback
44: parabolic
45: playback
46: prefabricate
47: quarterback
48: razorback
49: roadblock
50: sabbatical
51: snapback
52: strabismic
53: syllabic
54: tabernacle
55: tablecloth

AWK

The following one-liner entered into a Posix shell returns the same 55 words as other entries.

<lang awk>awk '/^[^bc]*a[^c]*b.*c/' unixdict.txt</lang>

BASIC

<lang basic>10 DEFINT A,B,C: DEFSTR W 20 OPEN "I",1,"unixdict.txt" 30 IF EOF(1) THEN END 40 LINE INPUT #1, W 50 A = INSTR(W,"a") 60 B = INSTR(W,"b") 70 C = INSTR(W,"c") 80 IF A>0 AND B>0 AND C>0 AND A<B AND B<C THEN PRINT W, 90 GOTO 30</lang>

Output:
aback         abacus        abc           abdicate      abduct
abeyance      abject        abreact       abscess       abscissa
abscissae     absence       abstract      abstracter    abstractor
adiabatic     aerobacter    aerobic       albacore      alberich
albrecht      algebraic     alphabetic    ambiance      ambuscade
aminobenzoic  anaerobic     arabic        athabascan    auerbach
diabetic      diabolic      drawback      fabric        fabricate
flashback     halfback      iambic        lampblack     leatherback
metabolic     nabisco       paperback     parabolic     playback
prefabricate  quarterback   razorback     roadblock     sabbatical
snapback      strabismic    syllabic      tabernacle    tablecloth

BCPL

<lang bcpl>get "libhdr"

let find(s, c) = valof $( for i=1 to s%0

       if s%i=c then resultis i
   resultis -1

$)

let match(word) = valof $( let a = find(word, 'a')

   let b = find(word, 'b')
   let c = find(word, 'c')
   resultis a ~= -1 & b ~= -1 & c ~= -1 & a<b & b<c

$)

let read(word) = valof $( let ch = ?

   word%0 := 0
   $(  ch := rdch()
       if ch = endstreamch then resultis false
       word%0 := word%0 + 1
       word%(word%0) := ch
   $) repeatuntil ch = '*N'
   resultis true

$)

let start() be $( let word = vec 63

   let file = findinput("unixdict.txt")
   test file = 0 then 
       writes("Cannot open unixdict.txt*N")
   else
   $(  selectinput(file)
       while read(word) if match(word) do writes(word)
       endread()
   $)

$)</lang>

Output:
aback
abacus
abc
abdicate
abduct
abeyance
abject
abreact
abscess
abscissa
abscissae
absence
abstract
abstracter
abstractor
adiabatic
aerobacter
aerobic
albacore
alberich
albrecht
algebraic
alphabetic
ambiance
ambuscade
aminobenzoic
anaerobic
arabic
athabascan
auerbach
diabetic
diabolic
drawback
fabric
fabricate
flashback
halfback
iambic
lampblack
leatherback
metabolic
nabisco
paperback
parabolic
playback
prefabricate
quarterback
razorback
roadblock
sabbatical
snapback
strabismic
syllabic
tabernacle
tablecloth

C

<lang c>#include <stdio.h>

  1. include <string.h>

int match(const char *word) {

   const char *a = strchr(word, 'a');
   const char *b = strchr(word, 'b');
   const char *c = strchr(word, 'c');
   return a && b && c && a<b && b<c;

}

int main() {

   char word[80];
   FILE *file = fopen("unixdict.txt", "r");
   if (!file) {
       fprintf(stderr, "Cannot open unixdict.txt");
       return -1;
   }
   
   while (!feof(file)) {
       fgets(word, sizeof(word), file);
       if(match(word)) printf("%s", word);
   }
   return 0;

}</lang>

Output:
aback
abacus
abc
abdicate
abduct
abeyance
abject
abreact
abscess
abscissa
abscissae
absence
abstract
abstracter
abstractor
adiabatic
aerobacter
aerobic
albacore
alberich
albrecht
algebraic
alphabetic
ambiance
ambuscade
aminobenzoic
anaerobic
arabic
athabascan
auerbach
diabetic
diabolic
drawback
fabric
fabricate
flashback
halfback
iambic
lampblack
leatherback
metabolic
nabisco
paperback
parabolic
playback
prefabricate
quarterback
razorback
roadblock
sabbatical
snapback
strabismic
syllabic
tabernacle
tablecloth

C#

Takes an optional command line for other character combinations. User can specify any reasonable number of unique characters. Caveat: see discussion page for issue about specifying repeated characters. <lang csharp>class Program {

   static void Main(string[] args) { int bi, i = 0; string chars = args.Length < 1 ? "abc" : args[0];
       foreach (var item in System.IO.File.ReadAllLines("unixdict.txt")) {
           int ai = -1; foreach (var ch in chars)
               if ((bi = item.IndexOf(ch)) > ai) ai = bi; else goto skip;
           System.Console.Write("{0,3} {1,-18} {2}", ++i, item, i % 5 == 0 ? "\n" : "");
       skip: ; } }

} </lang>

Output:

Without command line arguments:

  1 aback                2 abacus               3 abc                  4 abdicate             5 abduct
  6 abeyance             7 abject               8 abreact              9 abscess             10 abscissa
 11 abscissae           12 absence             13 abstract            14 abstracter          15 abstractor
 16 adiabatic           17 aerobacter          18 aerobic             19 albacore            20 alberich
 21 albrecht            22 algebraic           23 alphabetic          24 ambiance            25 ambuscade
 26 aminobenzoic        27 anaerobic           28 arabic              29 athabascan          30 auerbach
 31 diabetic            32 diabolic            33 drawback            34 fabric              35 fabricate
 36 flashback           37 halfback            38 iambic              39 lampblack           40 leatherback
 41 metabolic           42 nabisco             43 paperback           44 parabolic           45 playback
 46 prefabricate        47 quarterback         48 razorback           49 roadblock           50 sabbatical
 51 snapback            52 strabismic          53 syllabic            54 tabernacle          55 tablecloth

With command line argument "alw":

  1 afterglow            2 airflow              3 alewife              4 allentown            5 alleyway
  6 allow                7 allowance            8 alway                9 always              10 baldwin
 11 barlow              12 bartholomew         13 bungalow            14 caldwell            15 candlewick
 16 cauliflower         17 fallow              18 foamflower          19 galloway            20 gallows
 21 galway              22 halfway             23 hallow              24 halloween           25 hallway
 26 malawi              27 mallow              28 marlowe             29 marshmallow         30 mayflower
 31 metalwork           32 railway             33 sallow              34 saltwater           35 sandalwood
 36 shadflower          37 shallow             38 stalwart            39 tailwind            40 tallow

C++

<lang cpp>#include <cstdlib>

  1. include <fstream>
  2. include <iostream>

bool is_abc_word(const std::string& word) {

   bool a = false;
   bool b = false;
   for (char ch : word) {
       switch (ch) {
       case 'a':
           if (!a)
               a = true;
           break;
       case 'b':
           if (!b) {
               // fail if we haven't seen 'a' yet
               if (!a)
                   return false;
               b = true;
           }
           break;
       case 'c':
           // succeed iff we've seen 'b' already
           return b;
       }
   }
   return false;

}

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

   const char* filename(argc < 2 ? "unixdict.txt" : argv[1]);
   std::ifstream in(filename);
   if (!in) {
       std::cerr << "Cannot open file '" << filename << "'.\n";
       return EXIT_FAILURE;
   }
   std::string word;
   int n = 1;
   while (getline(in, word)) {
       if (is_abc_word(word))
           std::cout << n++ << ": " << word << '\n';
   }
   return EXIT_SUCCESS;

}</lang>

Output:
1: aback
2: abacus
3: abc
4: abdicate
5: abduct
6: abeyance
7: abject
8: abreact
9: abscess
10: abscissa
11: abscissae
12: absence
13: abstract
14: abstracter
15: abstractor
16: adiabatic
17: aerobacter
18: aerobic
19: albacore
20: alberich
21: albrecht
22: algebraic
23: alphabetic
24: ambiance
25: ambuscade
26: aminobenzoic
27: anaerobic
28: arabic
29: athabascan
30: auerbach
31: diabetic
32: diabolic
33: drawback
34: fabric
35: fabricate
36: flashback
37: halfback
38: iambic
39: lampblack
40: leatherback
41: metabolic
42: nabisco
43: paperback
44: parabolic
45: playback
46: prefabricate
47: quarterback
48: razorback
49: roadblock
50: sabbatical
51: snapback
52: strabismic
53: syllabic
54: tabernacle
55: tablecloth

Delphi

Translation of: C#

<lang Delphi> program ABC_words;

{$APPTYPE CONSOLE}

uses

 System.SysUtils,
 System.IoUtils;

var

 bi, ai, i: Integer;
 chars, item: string;
 ch: char;
 skip: boolean;

begin

 bi := 0;
 i := 0;
 chars := 'abc';
 if ParamCount > 0 then
   chars := ParamStr(1);
 writeln('Search words with letters "', chars, '"  in alphabetical order'#10);
 for item in TFile.ReadAllLines('unixdict.txt') do
 begin
   ai := -1;
   skip := false;
   for ch in chars do
   begin
     bi := item.IndexOf(ch);
     if bi > ai then
     begin
       ai := bi;
     end
     else
     begin
       skip := true;
       Break;
     end;
   end;
   if not skip then
   begin
     inc(i);
     write(i: 3, ' ', item.PadRight(18));
     if i mod 5 = 0 then
       writeln;
   end;
 end;
   
 {$IFNDEF UNIX} readln; {$ENDIF}

end.</lang>

Factor

<lang factor>USING: grouping io.encodings.ascii io.files kernel prettyprint sequences sets ;

"unixdict.txt" ascii file-lines [ "abc" within members "abc" = ] filter 5 group simple-table.</lang>

Output:
aback        abacus      abc        abdicate   abduct
abeyance     abject      abreact    abscess    abscissa
abscissae    absence     abstract   abstracter abstractor
adiabatic    aerobacter  aerobic    albacore   alberich
albrecht     algebraic   alphabetic ambiance   ambuscade
aminobenzoic anaerobic   arabic     athabascan auerbach
diabetic     diabolic    drawback   fabric     fabricate
flashback    halfback    iambic     lampblack  leatherback
metabolic    nabisco     paperback  parabolic  playback
prefabricate quarterback razorback  roadblock  sabbatical
snapback     strabismic  syllabic   tabernacle tablecloth

Forth

Works with: Gforth

<lang forth>: abc-word? ( addr u -- ? )

 false false { a b }
 0 do
   dup c@ case
     'a' of true to a endof
     'b' of a invert if unloop drop false exit then true to b endof
     'c' of unloop drop b exit endof
   endcase
   1+
 loop
 drop
 false ;

256 constant max-line

main
 0 0 { count fd-in }
 s" unixdict.txt" r/o open-file throw to fd-in
 begin
   here max-line fd-in read-line throw
 while
   here swap 2dup abc-word? if
     count 1+ to count
     count 2 .r ." : " type cr
   else
     2drop
   then
 repeat
 drop
 fd-in close-file throw ;

main bye</lang>

Output:
 1: aback
 2: abacus
 3: abc
 4: abdicate
 5: abduct
 6: abeyance
 7: abject
 8: abreact
 9: abscess
10: abscissa
11: abscissae
12: absence
13: abstract
14: abstracter
15: abstractor
16: adiabatic
17: aerobacter
18: aerobic
19: albacore
20: alberich
21: albrecht
22: algebraic
23: alphabetic
24: ambiance
25: ambuscade
26: aminobenzoic
27: anaerobic
28: arabic
29: athabascan
30: auerbach
31: diabetic
32: diabolic
33: drawback
34: fabric
35: fabricate
36: flashback
37: halfback
38: iambic
39: lampblack
40: leatherback
41: metabolic
42: nabisco
43: paperback
44: parabolic
45: playback
46: prefabricate
47: quarterback
48: razorback
49: roadblock
50: sabbatical
51: snapback
52: strabismic
53: syllabic
54: tabernacle
55: tablecloth

FreeBASIC

<lang freebasic>

  1. define NOTINSTRING 9999

function first_occ( s as string, letter as string ) as uinteger

   for i as ubyte = 1 to len(s)
       if mid(s,i,1) = letter then return i
   next i
   return NOTINSTRING - asc(letter)

end function

function is_abc( s as string ) as boolean

   if first_occ( s, "a" ) > first_occ( s, "b" ) then return false
   if first_occ( s, "b" ) > first_occ( s, "c" ) then return false
   if first_occ( s, "c" ) > len(s) then return false
   return true

end function

dim as string word dim as uinteger c = 0

open "unixdict.txt" for input as #1 while true

   line input #1, word
   if word="" then exit while
   if is_abc( word ) then
       c+=1
       print c;".   ";word
   end if

wend close #1</lang>

Output:
1.   aback
2.   abacus
3.   abc
4.   abdicate
5.   abduct
6.   abeyance
7.   abject
8.   abreact
9.   abscess
10.   abscissa
11.   abscissae
12.   absence
13.   abstract
14.   abstracter
15.   abstractor
16.   adiabatic
17.   aerobacter
18.   aerobic
19.   albacore
20.   alberich
21.   albrecht
22.   algebraic
23.   alphabetic
24.   ambiance
25.   ambuscade
26.   aminobenzoic
27.   anaerobic
28.   arabic
29.   athabascan
30.   auerbach
31.   diabetic
32.   diabolic
33.   drawback
34.   fabric
35.   fabricate
36.   flashback
37.   halfback
38.   iambic
39.   lampblack
40.   leatherback
41.   metabolic
42.   nabisco
43.   paperback
44.   parabolic
45.   playback
46.   prefabricate
47.   quarterback
48.   razorback
49.   roadblock
50.   sabbatical
51.   snapback
52.   strabismic
53.   syllabic
54.   tabernacle
55.   tablecloth

Go

<lang go>package main

import (

   "bytes"
   "fmt"
   "io/ioutil"
   "log"

)

func main() {

   wordList := "unixdict.txt"
   b, err := ioutil.ReadFile(wordList)
   if err != nil {
       log.Fatal("Error reading file")
   }
   bwords := bytes.Fields(b)
   count := 0
   fmt.Println("Based on first occurrences only, the ABC words in", wordList, "are:")
   for _, bword := range bwords {
       a := bytes.IndexRune(bword, 'a')
       b := bytes.IndexRune(bword, 'b')
       c := bytes.IndexRune(bword, 'c')
       if a >= 0 && b > a && c > b {
           count++
           fmt.Printf("%2d: %s\n", count, string(bword))
       }
   }

}</lang>

Output:
Based on first occurrences only, the ABC words in unixdict.txt are:
 1: aback
 2: abacus
 3: abc
 4: abdicate
 5: abduct
 6: abeyance
 7: abject
 8: abreact
 9: abscess
10: abscissa
11: abscissae
12: absence
13: abstract
14: abstracter
15: abstractor
16: adiabatic
17: aerobacter
18: aerobic
19: albacore
20: alberich
21: albrecht
22: algebraic
23: alphabetic
24: ambiance
25: ambuscade
26: aminobenzoic
27: anaerobic
28: arabic
29: athabascan
30: auerbach
31: diabetic
32: diabolic
33: drawback
34: fabric
35: fabricate
36: flashback
37: halfback
38: iambic
39: lampblack
40: leatherback
41: metabolic
42: nabisco
43: paperback
44: parabolic
45: playback
46: prefabricate
47: quarterback
48: razorback
49: roadblock
50: sabbatical
51: snapback
52: strabismic
53: syllabic
54: tabernacle
55: tablecloth

Haskell

<lang haskell>import Data.Maybe (isJust)


ABC WORDS -----------------------

isABC :: String -> Bool isABC s =

 isJust $
   afterChar 'a' "bc" s
     >>= afterChar 'b' "c"
     >>= afterChar 'c' ""

afterChar :: Char -> String -> String -> Maybe String afterChar c except = go

 where
   go [] = Nothing
   go (x : xs)
     | x `elem` except = Nothing
     | c == x = Just xs
     | otherwise = go xs

TEST -------------------------

main :: IO () main =

 readFile "unixdict.txt"
   >>= mapM_ print . zip [1 ..] . filter isABC . lines</lang>
Output:
(1,"aback")
(2,"abacus")
(3,"abc")
(4,"abdicate")
(5,"abduct")
(6,"abeyance")
(7,"abject")
(8,"abreact")
(9,"abscess")
(10,"abscissa")
(11,"abscissae")
(12,"absence")
(13,"abstract")
(14,"abstracter")
(15,"abstractor")
(16,"adiabatic")
(17,"aerobacter")
(18,"aerobic")
(19,"albacore")
(20,"alberich")
(21,"albrecht")
(22,"algebraic")
(23,"alphabetic")
(24,"ambiance")
(25,"ambuscade")
(26,"aminobenzoic")
(27,"anaerobic")
(28,"arabic")
(29,"athabascan")
(30,"auerbach")
(31,"diabetic")
(32,"diabolic")
(33,"drawback")
(34,"fabric")
(35,"fabricate")
(36,"flashback")
(37,"halfback")
(38,"iambic")
(39,"lampblack")
(40,"leatherback")
(41,"metabolic")
(42,"nabisco")
(43,"paperback")
(44,"parabolic")
(45,"playback")
(46,"prefabricate")
(47,"quarterback")
(48,"razorback")
(49,"roadblock")
(50,"sabbatical")
(51,"snapback")
(52,"strabismic")
(53,"syllabic")
(54,"tabernacle")
(55,"tablecloth")

Java

<lang java>import java.io.BufferedReader; import java.io.FileReader;

public class AbcWords {

   public static void main(String[] args) {
       String fileName = "unixdict.txt";
       String chars = "abc";
       for (int i = 0; i + 1 < args.length
               && args[i].length() > 1
               && args[i].charAt(0) == '-'; ++i) {
           switch (args[i].charAt(1)) {
           case 'f':
               fileName = args[++i];
               break;
           case 'c':
               chars = args[++i];
               break;
           }
       }
       
       try (BufferedReader reader = new BufferedReader(new FileReader(fileName))) {
           String line;
           int n = 0;
           while ((line = reader.readLine()) != null) {
               if (match(line, chars)) {
                   ++n;
                   System.out.printf("%3d: %-20s", n, line);
                   if (n % 3 == 0)
                       System.out.println();
               }
           }
           if (n > 0 && n % 3 != 0)
               System.out.println();
       } catch (Exception e)  {
           e.printStackTrace();
       }
   }
   // Returns true if word contains every character in chars in the
   // same order. chars may contain the same character more than once.
   private static boolean match(String word, String chars) {
       int length = chars.length();
       boolean[] seen = new boolean[length];
       int wordLength = word.length();
       for (int w = 0; w < wordLength; ++w) {
           char ch = word.charAt(w);
           int index = -1;
           for (int c = 0; c < length; ++c) {
               if (ch == chars.charAt(c) && !seen[c]) {
                   index = c;
                   break;
               }
           }
           if (index == -1)
               continue;
           if (index + 1 == length)
               return index == 0 ? true : seen[index - 1];
           if (index > 0 && !seen[index - 1])
               return false;
           seen[index] = true;
       }
       return false;
   }

}</lang>

Output:

With no command line arguments:

  1: aback                 2: abacus                3: abc                 
  4: abdicate              5: abduct                6: abeyance            
  7: abject                8: abreact               9: abscess             
 10: abscissa             11: abscissae            12: absence             
 13: abstract             14: abstracter           15: abstractor          
 16: adiabatic            17: aerobacter           18: aerobic             
 19: albacore             20: alberich             21: albrecht            
 22: algebraic            23: alphabetic           24: ambiance            
 25: ambuscade            26: aminobenzoic         27: anaerobic           
 28: arabic               29: athabascan           30: auerbach            
 31: diabetic             32: diabolic             33: drawback            
 34: fabric               35: fabricate            36: flashback           
 37: halfback             38: iambic               39: lampblack           
 40: leatherback          41: metabolic            42: nabisco             
 43: paperback            44: parabolic            45: playback            
 46: prefabricate         47: quarterback          48: razorback           
 49: roadblock            50: sabbatical           51: snapback            
 52: strabismic           53: syllabic             54: tabernacle          
 55: tablecloth

With command line arguments "-c pmm":

  1: anthropomorphism      2: epigrammatic          3: epimorphism         
  4: euphemism             5: optimism              6: optimum             
  7: pandemonium           8: pantomime             9: pantomimic          
 10: pemmican             11: persimmon            12: pessimism           
 13: pessimum             14: plummet              15: postmortem          
 16: pragmatism           17: praseodymium         18: premium             
 19: primitivism          20: programmable         21: programmed          
 22: programmer           23: programming          24: promethium          
 25: pummel               26: supremum

jq

Works with: jq

Works with gojq, the Go implementation of jq <lang jq>def is_abc_word:

 [index("a", "b", "c")]
 | all(.[]; . != null) and .[0] < .[1] and .[1] < .[2] ;

select(is_abc_word)</lang> Invocation: jq -rR -f abc-words.jq unixdict.txt

Output:

(synopsis)

aback
abacus
abc
...
aback
abacus
abc


Julia

See Alternade_words#Julia for the foreachword function. <lang julia>function isabcword(w, _)

   positions = [findfirst(c -> c == ch, w) for ch in "abc"]
   return all(!isnothing, positions) && issorted(positions) ? w : ""

end

foreachword("unixdict.txt", isabcword)

</lang>

Output:
Word source: unixdict.txt

aback          abacus         abc            abdicate       abduct         abeyance       
abject         abreact        abscess        abscissa       abscissae      absence
abstract       abstracter     abstractor     adiabatic      aerobacter     aerobic
albacore       alberich       albrecht       algebraic      alphabetic     ambiance
ambuscade      aminobenzoic   anaerobic      arabic         athabascan     auerbach       
diabetic       diabolic       drawback       fabric         fabricate      flashback
halfback       iambic         lampblack      leatherback    metabolic      nabisco
paperback      parabolic      playback       prefabricate   quarterback    razorback      
roadblock      sabbatical     snapback       strabismic     syllabic       tabernacle
tablecloth

Lua

<lang Lua>for word in io.lines('unixdict.txt') do

 if string.find(word, "^[^bc]*a[^c]*b.*c") then
   print(word)
 end

end</lang>

Nim

<lang Nim>import strutils

func isAbcWord(word: string): bool =

 let ia = word.find('a')
 if ia < 0: return false
 let ib = word.find('b')
 if ib < ia: return false
 let ic = word.find('c')
 if ic < ib: return false
 result = true

var count = 0 for word in "unixdict.txt".lines:

 if word.isAbcWord:
   inc count
   echo ($count).align(2), ' ', word</lang>
Output:
 1 aback
 2 abacus
 3 abc
 4 abdicate
 5 abduct
 6 abeyance
 7 abject
 8 abreact
 9 abscess
10 abscissa
11 abscissae
12 absence
13 abstract
14 abstracter
15 abstractor
16 adiabatic
17 aerobacter
18 aerobic
19 albacore
20 alberich
21 albrecht
22 algebraic
23 alphabetic
24 ambiance
25 ambuscade
26 aminobenzoic
27 anaerobic
28 arabic
29 athabascan
30 auerbach
31 diabetic
32 diabolic
33 drawback
34 fabric
35 fabricate
36 flashback
37 halfback
38 iambic
39 lampblack
40 leatherback
41 metabolic
42 nabisco
43 paperback
44 parabolic
45 playback
46 prefabricate
47 quarterback
48 razorback
49 roadblock
50 sabbatical
51 snapback
52 strabismic
53 syllabic
54 tabernacle
55 tablecloth

Perl

Outputs same 55 words everyone else finds. <lang perl>#!/usr/bin/perl

@ARGV = 'unixdict.txt'; print grep /^[^bc]*a[^c]*b.*c/, <>;</lang>

Phix

with javascript_semantics
function abc(string word) 
    integer {ia,ib,ic} = apply(true,find,{"abc",{word}})
    return ia>0 and ib>ia and ic>ib
end function
sequence words = filter(unix_dict(),abc)
printf(1,"%d abc words found: %s\n",{length(words),join(shorten(words,"",3),", ")})
Output:
55 abc words found: aback, abacus, abc, ..., syllabic, tabernacle, tablecloth

PL/I

<lang pli>abcWords: procedure options(main);

   declare dict file;
   open file(dict) title('unixdict.txt');
   on endfile(dict) stop;
   
   declare word char(32) varying, col fixed;
   col = 0;
   do while('1'b);
       get file(dict) list(word);
       
       declare (a, b, c) fixed;
       a = index(word, 'a');
       b = index(word, 'b');
       c = index(word, 'c');
       
       if a ^= 0 & b ^= 0 & c ^= 0 & a < b & b < c then do;
           put edit(word) (A(15));
           col = col + 1;
           if col = 5 then do;
               put skip;
               col = 0;
           end;
       end;
   end;    

end abcWords;</lang>

Output:
aback          abacus         abc            abdicate       abduct
abeyance       abject         abreact        abscess        abscissa
abscissae      absence        abstract       abstracter     abstractor
adiabatic      aerobacter     aerobic        albacore       alberich
albrecht       algebraic      alphabetic     ambiance       ambuscade
aminobenzoic   anaerobic      arabic         athabascan     auerbach
diabetic       diabolic       drawback       fabric         fabricate
flashback      halfback       iambic         lampblack      leatherback
metabolic      nabisco        paperback      parabolic      playback
prefabricate   quarterback    razorback      roadblock      sabbatical
snapback       strabismic     syllabic       tabernacle     tablecloth

Processing

<lang processing>String[] words;

void setup() {

 words = loadStrings("unixdict.txt");
 int count = 1;
 for (int i = 0; i < words.length; i++) {
   if (isAbcWord(words[i])) {
     println(count + " " + words[i]);
     count++;
   }
 }

}

boolean isAbcWord(String word) {

 if (word.contains("a") && word.indexOf("a") < word.indexOf("b") && word.indexOf("b") < word.indexOf("c")) {
   return true;
 }
 return false;

}</lang>

Output:
1 aback
2 abacus
3 abc
4 abdicate
5 abduct
6 abeyance
7 abject
8 abreact
9 abscess
10 abscissa
11 abscissae
12 absence
13 abstract
14 abstracter
15 abstractor
16 adiabatic
17 aerobacter
18 aerobic
19 albacore
20 alberich
21 albrecht
22 algebraic
23 alphabetic
24 ambiance
25 ambuscade
26 aminobenzoic
27 anaerobic
28 arabic
29 athabascan
30 auerbach
31 diabetic
32 diabolic
33 drawback
34 fabric
35 fabricate
36 flashback
37 halfback
38 iambic
39 lampblack
40 leatherback
41 metabolic
42 nabisco
43 paperback
44 parabolic
45 playback
46 prefabricate
47 quarterback
48 razorback
49 roadblock
50 sabbatical
51 snapback
52 strabismic
53 syllabic
54 tabernacle
55 tablecloth

Python

Outputs the same 55 words as other examples when entered in a Posix terminal shell

<lang python>python -c ' import sys for ln in sys.stdin:

   if "a" in ln and ln.find("a") < ln.find("b") < ln.find("c"):
       print(ln.rstrip())

' < unixdict.txt </lang>

Or a functionally composed variant, with a predicate which takes a single recursive pass through the characters of each word:

<lang python>ABC Words


  1. isABC :: String -> Bool

def isABC(s):

   True if s contains 'a', 'b' and 'c', with the
      first occurrences of each in that order.
   
   return None != bind(
       bind(
           residue('a')('bc')(s)
       )(
           residue('b')('c')
       )
   )(
       residue('c')()
   )


  1. residue Char -> String -> String -> Maybe String

def residue(c):

   Any characters remaining in s after c, unless
      c is preceded by excluded characters.
   
   def excluding(cs):
       def go(s):
           if s:
               x = s[0]
               return None if x in cs else (
                   s[1:] if c == x else go(s[1:])
               )
           else:
               return None
       return go
   return excluding


  1. ------------------------- TEST -------------------------
  2. main :: IO ()

def main():

   All words matching the isABC predicate
      in a local copy of unixdict.txt
   
   for x in enumerate(
       filter(
           isABC,
           readFile('unixdict.txt').splitlines()
       ),
       start=1
   ):
       print(x)


  1. ----------------------- GENERIC ------------------------
  1. bind (>>=) :: Maybe a -> (a -> Maybe b) -> Maybe b

def bind(m):

   Composition of a sequence of (a -> None | b) functions.
      If m is None, it is passed straight through.
      If m is x, the result is an application
      of the (a -> None | b) function (mf) to x.
   
   def go(mf):
       return m if None is m else mf(m)
   return go


  1. readFile :: FilePath -> IO String

def readFile(fp):

   The contents of any file at the path
      derived by expanding any ~ in fp.
   
   with open(fp, 'r', encoding='utf-8') as f:
       return f.read()


  1. MAIN ---

if __name__ == '__main__':

   main()</lang>
Output:
(1, 'aback')
(2, 'abacus')
(3, 'abc')
(4, 'abdicate')
(5, 'abduct')
(6, 'abeyance')
(7, 'abject')
(8, 'abreact')
(9, 'abscess')
(10, 'abscissa')
(11, 'abscissae')
(12, 'absence')
(13, 'abstract')
(14, 'abstracter')
(15, 'abstractor')
(16, 'adiabatic')
(17, 'aerobacter')
(18, 'aerobic')
(19, 'albacore')
(20, 'alberich')
(21, 'albrecht')
(22, 'algebraic')
(23, 'alphabetic')
(24, 'ambiance')
(25, 'ambuscade')
(26, 'aminobenzoic')
(27, 'anaerobic')
(28, 'arabic')
(29, 'athabascan')
(30, 'auerbach')
(31, 'diabetic')
(32, 'diabolic')
(33, 'drawback')
(34, 'fabric')
(35, 'fabricate')
(36, 'flashback')
(37, 'halfback')
(38, 'iambic')
(39, 'lampblack')
(40, 'leatherback')
(41, 'metabolic')
(42, 'nabisco')
(43, 'paperback')
(44, 'parabolic')
(45, 'playback')
(46, 'prefabricate')
(47, 'quarterback')
(48, 'razorback')
(49, 'roadblock')
(50, 'sabbatical')
(51, 'snapback')
(52, 'strabismic')
(53, 'syllabic')
(54, 'tabernacle')
(55, 'tablecloth')

Quackery

<lang Quackery> [ true swap

   behead swap
   witheach 
     [ tuck < not if
         [ dip not 
           conclude ] ] 
   drop ]               is ascending ( [ --> b )
 [ [] swap 
   $ "abc" witheach
     [ over find 
       swap dip join ] 
    size join
    ascending ]         is abcword   ( $ --> b )

 [] 
 $ "rosetta/unixdict.txt" sharefile drop nest$
 witheach 
   [ dup abcword iff
       [ nested join ]
     else drop ] 
 dup size echo say " words found." cr
 70 wrap$</lang>
Output:
55 words found.

aback abacus abc abdicate abduct abeyance abject abreact abscess
abscissa abscissae absence abstract abstracter abstractor adiabatic
aerobacter aerobic albacore alberich albrecht algebraic alphabetic
ambiance ambuscade aminobenzoic anaerobic arabic athabascan auerbach
diabetic diabolic drawback fabric fabricate flashback halfback iambic
lampblack leatherback metabolic nabisco paperback parabolic playback
prefabricate quarterback razorback roadblock sabbatical snapback
strabismic syllabic tabernacle tablecloth

Racket

<lang racket>#lang racket

(for ((i (in-naturals 1))

     (w (filter (curry regexp-match #rx"^[^bc]*a[^c]*b.*c.*$")
         (file->lines "../../data/unixdict.txt"))))
 (printf "~a\t~a~%" i w))</lang>
Output:

Output is elided... it's the same list of words in every other implementation

1	aback
2	abacus
3	abc
4	abdicate
5	abduct
6	abeyance
7	abject
8	abreact
9	abscess
10	abscissa
11	abscissae
12	absence
...
50	sabbatical
51	snapback
52	strabismic
53	syllabic
54	tabernacle
55	tablecloth

Raku

<lang perl6>put display 'unixdict.txt'.IO.words».fc.grep({ (.index('a')//next) < (.index('b')//next) < (.index('c')//next) }),

    :11cols, :fmt('%-12s');

sub display ($list, :$cols = 10, :$fmt = '%6d', :$title = "{+$list} matching:\n" ) {

   cache $list;
   $title ~ $list.batch($cols)».fmt($fmt).join: "\n"

}</lang>

Output:
55 matching:
aback        abacus       abc          abdicate     abduct       abeyance     abject       abreact      abscess      abscissa     abscissae   
absence      abstract     abstracter   abstractor   adiabatic    aerobacter   aerobic      albacore     alberich     albrecht     algebraic   
alphabetic   ambiance     ambuscade    aminobenzoic anaerobic    arabic       athabascan   auerbach     diabetic     diabolic     drawback    
fabric       fabricate    flashback    halfback     iambic       lampblack    leatherback  metabolic    nabisco      paperback    parabolic   
playback     prefabricate quarterback  razorback    roadblock    sabbatical   snapback     strabismic   syllabic     tabernacle   tablecloth 

REXX

This REXX version doesn't care what order the words in the dictionary are in,   nor does it care what
case  (lower/upper/mixed)  the words are in,   the search for the   ABC   words is   caseless.

It also allows the   (ABC)   characters to be specified on the command line (CL) as well as the dictionary file identifier. <lang rexx>/*REXX program finds all the caseless alternade words (within an identified dictionary).*/ parse arg minL iFID . /*obtain optional arguments from the CL*/ if minL== | minL=="," then minL= 6 /*Not specified? Then use the default.*/ if iFID== | iFID=="," then iFID='unixdict.txt' /* " " " " " " */ @.= /*default value of any dictionary word.*/

           do #=1  while lines(iFID)\==0        /*read each word in the file  (word=X).*/
           x= strip( linein( iFID) )            /*pick off a word from the input line. */
           $.#= x;       upper x;       @.x= .  /*save: original case and the semaphore*/
           end   /*#*/                          /* [↑]   semaphore name is uppercased. */
  1. = # - 1 /*adjust word count because of DO loop.*/

finds= 0 /*count of the alternade words found. */ say copies('─', 30) # "words in the dictionary file: " iFID say

       do j=1  for #;           L= length($.j)  /*process all the words that were found*/
       if L<minL  then iterate                  /*Is word too short?   Then ignore it. */
       p.=                                      /*initialize 2 parts of alternade word.*/
            do k=1  for L;         _= k // 2    /*build the  "   "    "      "      "  */
            p._= p._  ||  substr($.j, k, 1)     /*append to one part of alternade word.*/
            end   /*k*/
       parse upper value  p.0 p.1  with  p0 p1  /*obtain the uppercase alternade parts.*/
       if @.p0== | @.p1==  then iterate     /*either parts of alternade not extant?*/
       finds= finds + 1                         /*bump the  count  of alternades found.*/
       say right(left($.j, 20), 25)    left(p.1, 10)    left(p.0, 10)   /*indent a bit.*/
       end        /*j*/
                                                /*stick a fork in it,  we're all done. */

say copies('─',30) finds ' alternade words found with a minimum length of ' minL</lang>

output   when using the default input:
────────────────────────────── 25104 words in the dictionary file:  unixdict.txt
          aback
          abacus
          abc
          abdicate
          abduct
          abeyance
          abject
          abreact
          abscess
          abscissa
          abscissae
          absence
          abstract
          abstracter
          abstractor
          adiabatic
          aerobacter
          aerobic
          albacore
          alberich
          albrecht
          algebraic
          alphabetic
          ambiance
          ambuscade
          aminobenzoic
          anaerobic
          arabic
          athabascan
          auerbach
          diabetic
          diabolic
          drawback
          fabric
          fabricate
          flashback
          halfback
          iambic
          lampblack
          leatherback
          metabolic
          nabisco
          paperback
          parabolic
          playback
          prefabricate
          quarterback
          razorback
          roadblock
          sabbatical
          snapback
          strabismic
          syllabic
          tabernacle
          tablecloth
────────────────────────────── 55  "ABC" words found using the characters:  abc
output   when using the  (vowels in order)  input:     aeiou
────────────────────────────── 25104 words in the dictionary file:  unixdict.txt
          adventitious
          facetious
────────────────────────────── 2  "ABC" words found using the characters:  aeiou

Ring

<lang ring> cStr = read("unixdict.txt") wordList = str2list(cStr) num = 0

see "ABC words are:" + nl

for n = 1 to len(wordList)

   bool1 = substr(wordList[n],"a")
   bool2 = substr(wordList[n],"b")
   bool3 = substr(wordList[n],"c")
   bool4 = bool1 > 0 and bool2 > 0 and bool3 > 0
   bool5 = bool2 > bool1 and bool3 > bool2
   if bool4 = 1 and bool5 = 1
      num = num + 1
      see "" + num + ". " + wordList[n] + nl
   ok

next </lang> Output:

ABC words are:
1. aback
2. abacus
3. abc
4. abdicate
5. abduct
6. abeyance
7. abject
8. abreact
9. abscess
10. abscissa
11. abscissae
12. absence
13. abstract
14. abstracter
15. abstractor
16. adiabatic
17. aerobacter
18. aerobic
19. albacore
20. alberich
21. albrecht
22. algebraic
23. alphabetic
24. ambiance
25. ambuscade
26. aminobenzoic
27. anaerobic
28. arabic
29. athabascan
30. auerbach
31. diabetic
32. diabolic
33. drawback
34. fabric
35. fabricate
36. flashback
37. halfback
38. iambic
39. lampblack
40. leatherback
41. metabolic
42. nabisco
43. paperback
44. parabolic
45. playback
46. prefabricate
47. quarterback
48. razorback
49. roadblock
50. sabbatical
51. snapback
52. strabismic
53. syllabic
54. tabernacle
55. tablecloth

Ruby

translation from Perl <lang ruby>puts File.open("unixdict.txt").grep(/^[^bc]*a[^c]*b.*c/) </lang>

Output:

Same 55 words

aback
abacus
abc
abdicate
abduct
abeyance
abject
abreact
abscess
...
quarterback
razorback
roadblock
sabbatical
snapback
strabismic
syllabic
tabernacle
tablecloth

Swift

<lang swift>import Foundation

func loadDictionary(_ path: String) throws -> [String] {

   let contents = try String(contentsOfFile: path, encoding: String.Encoding.ascii)
   return contents.components(separatedBy: "\n")

}

func isAbcWord(_ word: String) -> Bool {

   var a = false
   var b = false
   for ch in word {
       switch (ch) {
       case "a":
           if !a {
               a = true
           }
       case "b":
           if !b {
               if !a {
                   return false
               }
               b = true
           }
       case "c":
           return b
       default:
           break
       }
   }
   return false

}

do {

   let dictionary = try loadDictionary("unixdict.txt")
   var n = 1
   for word in dictionary {
       if isAbcWord(word) {
           print("\(n): \(word)")
           n += 1
       }
   }

} catch {

   print(error)

}</lang>

Output:
1: aback
2: abacus
3: abc
4: abdicate
5: abduct
6: abeyance
7: abject
8: abreact
9: abscess
10: abscissa
11: abscissae
12: absence
13: abstract
14: abstracter
15: abstractor
16: adiabatic
17: aerobacter
18: aerobic
19: albacore
20: alberich
21: albrecht
22: algebraic
23: alphabetic
24: ambiance
25: ambuscade
26: aminobenzoic
27: anaerobic
28: arabic
29: athabascan
30: auerbach
31: diabetic
32: diabolic
33: drawback
34: fabric
35: fabricate
36: flashback
37: halfback
38: iambic
39: lampblack
40: leatherback
41: metabolic
42: nabisco
43: paperback
44: parabolic
45: playback
46: prefabricate
47: quarterback
48: razorback
49: roadblock
50: sabbatical
51: snapback
52: strabismic
53: syllabic
54: tabernacle
55: tablecloth

Tcl

<lang tcl>proc is_abc_word word { regexp {^[^bc]*a[^c]*b.*c} $word }

set res [lmap w [read [open unixdict.txt]] { if {[is_abc_word $w]} {set w} else continue }]

puts "Found [llength $res] words:" puts [join $res \n]</lang>

Output:
$ tclsh abc_words.tcl
Found 55 words:
aback
abacus
abc
abdicate
abduct
abeyance
abject
abreact
abscess
abscissa
abscissae
absence
abstract
abstracter
abstractor
adiabatic
aerobacter
aerobic
albacore
alberich
albrecht
algebraic
alphabetic
ambiance
ambuscade
aminobenzoic
anaerobic
arabic
athabascan
auerbach
diabetic
diabolic
drawback
fabric
fabricate
flashback
halfback
iambic
lampblack
leatherback
metabolic
nabisco
paperback
parabolic
playback
prefabricate
quarterback
razorback
roadblock
sabbatical
snapback
strabismic
syllabic
tabernacle
tablecloth

Wren

Library: Wren-fmt

<lang ecmascript>import "io" for File import "/fmt" for Fmt

var wordList = "unixdict.txt" // local copy var words = File.read(wordList).trimEnd().split("\n") var count = 0 System.print("Based on first occurrences only, the ABC words in %(wordList) are:") for (word in words) {

   var a = word.indexOf("a")
   var b = word.indexOf("b")
   var c = word.indexOf("c")
   if (a >= 0 && b > a && c > b) {
       count = count + 1
       Fmt.print("$2d: $s", count, word)
   }

}</lang>

Output:
Based on first occurrences only, the ABC words in unixdict.txt are:
 1: aback
 2: abacus
 3: abc
 4: abdicate
 5: abduct
 6: abeyance
 7: abject
 8: abreact
 9: abscess
10: abscissa
11: abscissae
12: absence
13: abstract
14: abstracter
15: abstractor
16: adiabatic
17: aerobacter
18: aerobic
19: albacore
20: alberich
21: albrecht
22: algebraic
23: alphabetic
24: ambiance
25: ambuscade
26: aminobenzoic
27: anaerobic
28: arabic
29: athabascan
30: auerbach
31: diabetic
32: diabolic
33: drawback
34: fabric
35: fabricate
36: flashback
37: halfback
38: iambic
39: lampblack
40: leatherback
41: metabolic
42: nabisco
43: paperback
44: parabolic
45: playback
46: prefabricate
47: quarterback
48: razorback
49: roadblock
50: sabbatical
51: snapback
52: strabismic
53: syllabic
54: tabernacle
55: tablecloth

XPL0

<lang XPL0>string 0; \use zero-terminated strings int I, J, K, Ch, Len; char Word(100); \(longest word in unixdict.txt is 22 chars) def LF=$0A, CR=$0D, EOF=$1A; [FSet(FOpen("unixdict.txt", 0), ^I); \open dictionary and set it to device 3 OpenI(3); repeat I:= 0;

       loop    [repeat Ch:= ChIn(3) until Ch # CR;     \remove possible CR
               if Ch=LF or Ch=EOF then quit;
               Word(I):= Ch;
               I:= I+1;
               ];
       Word(I):= 0;                    \terminate string
       Len:= I;
       for I:= 0 to Len-1 do
           if Word(I)=^a then
               [for J:= 0 to Len-1 do
                   if Word(J)=^b then
                       [for K:= 0 to Len-1 do
                           if Word(K)=^c then
                               [if K>J & J>I then
                                   [Text(0, Word);  CrLf(0)];
                               K:= Len;
                               ];
                       J:= Len;
                       ];
               I:= Len;
               ];

until Ch = EOF; ]</lang>

Output:
aback
abacus
abc
abdicate
abduct
abeyance
abject
abreact
abscess
abscissa
abscissae
absence
abstract
abstracter
abstractor
adiabatic
aerobacter
aerobic
albacore
alberich
albrecht
algebraic
alphabetic
ambiance
ambuscade
aminobenzoic
anaerobic
arabic
athabascan
auerbach
diabetic
diabolic
drawback
fabric
fabricate
flashback
halfback
iambic
lampblack
leatherback
metabolic
nabisco
paperback
parabolic
playback
prefabricate
quarterback
razorback
roadblock
sabbatical
snapback
strabismic
syllabic
tabernacle
tablecloth