Sort three variables

From Rosetta Code
Task
Sort three variables
You are encouraged to solve this task according to the task description, using any language you may know.
Task

Sort   (the values of)   three variables   (X,   Y,   and   Z)   that contain any value   (numbers and/or literals).

If that isn't possible in your language, then just sort numbers   (and note if they can be floating point, integer, or other).

I.E.:   (for the three variables   x,   y,   and   z),   where:

                        x =  'lions, tigers, and'
                        y =  'bears, oh my!'
                        z =  '(from the "Wizard of OZ")'

After sorting, the three variables would hold:

                        x =  '(from the "Wizard of OZ")'
                        y =  'bears, oh my!'
                        z =  'lions, tigers, and'

For numeric value sorting, use: I.E.:   (for the three variables   x,   y,   and   z),   where:

                        x =  77444
                        y =    -12
                        z =      0

After sorting, the three variables would hold:

                        x =    -12
                        y =      0
                        z =  77444

The variables should contain some form of a number, but specify if the algorithm used can be for floating point or integers.   Note any limitations.

The values may or may not be unique.

The method used for sorting can be any algorithm;   the goal is to use the most idiomatic in the computer programming language used.

More than one algorithm could be shown if one isn't clearly the better choice.


One algorithm could be:

                          store the three variables   x, y, and z
                                 into an array (or a list)   A
                         
                          sort  (the three elements of)  the array   A
                         
                          extract the three elements from the array and place them in the
                                 variables x, y, and z   in order of extraction


Another algorithm   (only for numeric values):

       x= 77444 
       y=   -12 
       z=     0      
    low= x                                          
    mid= y                                          
   high= z 
      x= min(low,  mid,  high)            /*determine the lowest value of X,Y,Z. */    
      z= max(low,  mid,  high)            /*    "      "  highest  "    " " " "  */    
      y=     low + mid + high - x - z     /*    "      "  middle   "    " " " "  */      


Show the results of the sort here on this page using at least the values of those shown above.

11l

V x = 77444
V y =   -12
V z =     0
(x, y, z) = tuple_sorted((x, y, z))
print(x‘ ’y‘ ’z)

V xs = ‘lions, tigers, and’
V ys = ‘bears, oh my!’
V zs = ‘(from the "Wizard of OZ")’
(xs, ys, zs) = sorted([xs, ys, zs])
print(xs"\n"ys"\n"zs)
Output:
-12 0 77444
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and

8086 Assembly

Sorting Unsigned Integers

mov ax,6FFFh
mov bx,3456h
mov cx,0

;We'll consider these sorted when ax <= bx <= cx.

SortRegisters proc
cmp ax,bx
jbe continue
     ;if we got here, ax > bx. We don't know the relationship between bx and cx at this time.
     cmp ax,cx
     jbe swap_ax_and_bx
        ;if we got here, ax > bx, and bx > cx. Therefore all we need to do is swap ax and cx, and we're done.
        xchg ax,cx
        jmp endOfProc

swap ax_and_bx:
;if we got here, ax > bx, and ax <= cx. So all we have to do is swap ax and bx, and we're done
xchg ax,bx
jmp end  ;back to top
        

continue:  ;if we got here, ax <= bx.
cmp bx,cx
jbe end
          ;if we got here, ax <= bx, and bx > cx. Therefore all we need to do is swap bx and cx, and we're done.
          xchg bx,cx


endOfProc: ;if we got here, ax <= bx, and bx <= cx. Therefore, ax <= bx <=cx and we are done.
;

SortRegisters endp

Ada

with Ada.Text_IO;
with Ada.Strings.Unbounded;

procedure Sort_Three is

   generic
      type Element_Type is private;
      with function "<" (Left, Right : in Element_Type) return Boolean;
   procedure Generic_Sort (X, Y, Z : in out Element_Type);

   procedure Generic_Sort (X, Y, Z : in out Element_Type)
   is
      procedure Swap (Left, Right : in out Element_Type) is
         T : constant Element_Type := Left;
      begin
         Left := Right;
         Right := T;
      end Swap;
   begin
      if Y < X then Swap (X, Y); end if;
      if Z < Y then Swap (Y, Z); end if;
      if Y < X then Swap (X, Y); end if;
   end Generic_Sort;

   procedure Test_Unbounded_Sort is
      use Ada.Text_IO;
      use Ada.Strings.Unbounded;

      X : Unbounded_String := To_Unbounded_String ("lions, tigers, and");
      Y : Unbounded_String := To_Unbounded_String ("bears, oh my!");
      Z : Unbounded_String := To_Unbounded_String ("(from the ""Wizard of OZ"")");

      procedure Sort is
         new Generic_Sort (Unbounded_String, "<");
   begin
      Sort (X, Y, Z);
      Put_Line (To_String (X));
      Put_Line (To_String (Y));
      Put_Line (To_String (Z));
      New_Line;
   End Test_Unbounded_Sort;

   procedure Test_Integer_Sort is

      use Ada.Text_IO;

      procedure Sort is
         new Generic_Sort (Integer, "<");

      X : Integer := 77444;
      Y : Integer :=   -12;
      Z : Integer :=     0;
   begin
      Sort (X, Y, Z);
      Put_Line (X'Image);
      Put_Line (Y'Image);
      Put_Line (Z'Image);
      New_Line;
   end Test_Integer_Sort;

begin
   Test_Unbounded_Sort;
   Test_Integer_Sort;
end Sort_Three;
Output:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and

-12
 0
 77444

Aime

integer a, b, c;
index i;
text x, y, z;
record r;

x = "lions, tigers, and";
y = "bears, oh my!";
z = "(from the \"Wizard of OZ\")";

r.fit(x, x, y, y, z, z);

x = r.rf_pick;
y = r.rf_pick;
z = r.rf_pick;

o_form("~\n~\n~\n", x, y, z);

a = 77444;
b = -12;
c = 0;

i.fit(a, a, b, b, c, c);

a = i.if_pick;
b = i.if_pick;
c = i.if_pick;

o_form("~\n~\n~\n", a, b, c);
Output:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and
-12
0
77444

ALGOL 68

This uses Algol 68's UNION facility which allows a variable to have values of a number of types whilst maintaining Algol 68's strong-typing.
Assignment allows any value of one of the UNION MODEs to be directly assigned to the variable. When using the variable, its MODE (type) and value must be tested and extracted using a CASE construct.
As the task only requires sorting three values, we use a simple, three-element specific sort routine.

BEGIN
    # MODE that can hold integers and strings - would need to be extended to #
    # allow for other types                                                  #
    MODE INTORSTRING = UNION( INT, STRING );
    # returns TRUE if a is an INT, FALSE otherwise #
    OP   ISINT    = ( INTORSTRING a )BOOL:   CASE a IN (INT):      TRUE OUT FALSE ESAC;
    # returns TRUE if a is an INT, FALSE otherwise #
    OP   ISSTRING = ( INTORSTRING a )BOOL:   CASE a IN (STRING):   TRUE OUT FALSE ESAC;
    # returns the integer in a or 0 if a isn't an integer #
    OP   TOINT    = ( INTORSTRING a )INT:    CASE a IN (INT i):    i    OUT 0     ESAC;
    # returns the string in a or "" if a isn't a string #
    OP   TOSTRING = ( INTORSTRING a )STRING: CASE a IN (STRING s): s    OUT ""    ESAC;
    # returns TRUE if a < b, FALSE otherwise #
    # a and b must have the same type #
    PRIO LESSTHAN = 4;
    OP   LESSTHAN = ( INTORSTRING a, b )BOOL:
        IF  ISSTRING a AND ISSTRING b THEN
            # both strings #
            TOSTRING a < TOSTRING b
        ELIF ISINT a AND ISINT b THEN
            # both integers #
            TOINT a < TOINT b
        ELSE
            # different MODEs #
            FALSE
        FI # LESSTHAN # ;
    # exchanges the values of a and b #
    PRIO SWAP = 9;
    OP   SWAP = ( REF INTORSTRING a, b )VOID: BEGIN INTORSTRING t := a; a := b; b := t END;
    # sorts a, b and c #
    PROC sort 3 = ( REF INTORSTRING a, b, c )VOID:
    BEGIN
        IF b LESSTHAN a THEN a SWAP b FI;
        IF c LESSTHAN a THEN a SWAP c FI;
        IF c LESSTHAN b THEN b SWAP c FI
    END # sort 3 # ;

    # task test cases #
    INTORSTRING x, y, z;
    x := "lions, tigers, and";
    y := "bears, oh my!";
    z := "(from the ""Wizard of OZ"")";
    sort 3( x, y, z );
    print( ( x, newline, y, newline, z, newline ) );
    x := 77444;
    y := -12;
    z := 0;
    sort 3( x, y, z );
    print( ( x, newline, y, newline, z, newline ) )
END
Output:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and
        -12
         +0
     +77444

Amazing Hopper

#include <basico.h>

algoritmo

    x = 77444, y = -12.5, z = 0
    low=x, midd=y, high=z
    
    imprimir("BEFORE:\nX = ",x, " Y = ",y, " Z = ",z,NL)
    #basic{
        x = min( min( low,midd),high)
        z = max( max( low,midd),high)
        y = low + midd + high - x - z
    }

    imprimir("\nAFTER:\nX = ",x, " Y = ",y, " Z = ",z,NL,NL)

    x = "lions, tigers, and"
    y = "bears, oh my!"
    z = "(from the \"Wizard of OZ\")"
    imprimir("BEFORE:\nX = ",x, "\nY = ",y, "\nZ = ",z,NL)
    #(x > y), entonces { intercambiar( x,y) }
    #(y > z), entonces {
        intercambiar (y,z )
        #(x > y), entonces { intercambiar( x,y ) }
    }

    imprimir("\nAFTER:\nX = ",x, "\nY = ",y, "\nZ = ",z,NL,NL) 

    p = {}
    '"lions, tigers, and",77444,"bears, oh my!",-12.7,0,"(from the \"Wizard of OZ\")"'
    enlistar en 'p'

    fijar separador 'NL'
    
    imprimir("BEFORE:\n",p,NL)
    matriz.ordenar(p)
    
    imprimir("\nAFTER:\n",p,NL)


terminar
Output:
$ hopper3 basica/sort3var.bas 
BEFORE:
X = 77444 Y = -12.500000 Z = 0

AFTER:
X = -12.500000 Y = 0.000000 Z = 77444.000000

BEFORE:
X = lions, tigers, and
Y = bears, oh my!
Z = (from the "Wizard of OZ")

AFTER:
X = (from the "Wizard of OZ")
Y = bears, oh my!
Z = lions, tigers, and

BEFORE:
lions, tigers, and
77444
bears, oh my!
-12.700000
0
(from the "Wizard of OZ")

AFTER:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and
-12.700000
0
77444

APL

Works in Dyalog APL. Assumes x,y,z are already defined.

x y z{[]}x y z

Uses destructuring assignment syntax.

AppleScript

set x to "lions, tigers, and"
set y to "bears, oh my!"
set z to "(from the \"Wizard of OZ\")"

if (x > y) then set {x, y} to {y, x}
if (y > z) then
    set {y, z} to {z, y}
    if (x > y) then set {x, y} to {y, x}
end if

return {x, y, z}
Output:
{"(from the \"Wizard of OZ\")", "bears, oh my!", "lions, tigers, and"}
set x to 77444
set y to -12
set z to 0

if (x > y) then set {x, y} to {y, x}
if (y > z) then
    set {y, z} to {z, y}
    if (x > y) then set {x, y} to {y, x}
end if

return {x, y, z}
Output:
{-12, 0, 77444}

Longer, but more efficiently:

set x to "lions, tigers, and"
set y to "bears, oh my!"
set z to "(from the \"Wizard of OZ\")"

tell x
    if (it > y) then
        set x to y
        set y to it
    end if
end tell
tell z
    if (it < y) then
        set z to y
        if (it < x) then
            set y to x
            set x to it
        else
            set y to it
        end if
    end if
end tell

return {x, y, z}

Arturo

x: {lions, tigers, and}
y: {bears, oh my!}
z: {(from the "Wizard of OZ")}

print join.with:"\n" sort @[x y z]

x: 125
y: neg 2
z: pi

print sort @[x y z]
Output:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and
-2 3.141592653589793 125

AutoHotkey

SortThreeVariables(ByRef x,ByRef y,ByRef z){
  obj := []
  for k, v in (var := StrSplit("x,y,z", ","))
    obj[%v%] := true
  for k, v in obj
    temp := var[A_Index], %temp% := k
}
Examples:
x =  lions, tigers, and
y =  bears, oh my!
z =  (from the "Wizard of OZ")
SortThreeVariables(x,y,z)
MsgBox % x "`n" y "`n" z

x =  77444
y =    -12
z =      0
SortThreeVariables(x,y,z)
MsgBox % x "`n" y "`n" z
return
Outputs:
---------------------------
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and
---------------------------
-12
0
77444
---------------------------

BCPL

BCPL is typeless: every variable is simply a machine word, and it is the operators that are used that decide how to treat their input. Therefore, this function uses an external comparator function to decide how the three variables should be ordered.

The code below uses sort3 to sort both integers and strings (i.e., pointers to vectors of characters packed into machine words). To make it work with floating-point numbers, on a compiler that supports them, all one would need to do is define a third comparator.

get "libhdr"

// Sort 3 variables using a comparator.
// X, Y and Z are pointers.
let sort3(comp, x, y, z) be
$(  sort2(comp, x, y)
    sort2(comp, x, z)
    sort2(comp, y, z)
$)
and sort2(comp, x, y) be
    if comp(!x, !y) > 0
    $(  let t = !x
        !x := !y
        !y := t
    $)

// Integer and string comparators
let intcomp(x, y) = x - y
let strcomp(x, y) = valof
$(  for i=1 to min(x%0, y%0)
        unless x%i = y%i
            resultis intcomp(x%i, y%i)
    resultis intcomp(x%0, y%0)
$)
and min(x, y) = x < y -> x, y

// Run the function on both ints and strings
let start() be
$(  printAndSort(writen, intcomp, 7444, -12, 0)
    printAndSort(writes, strcomp,
        "lions, tigers, and",
        "bears, oh my!",
        "(from the *"Wizard of OZ*")")
$)

// Print the 3 values, sort them, and print them again
and printAndSort(printfn, comp, x, y, z) be
$(  print3(printfn, x, y, z) ; writes("*N")
    sort3(comp, @x, @y, @z)
    print3(printfn, x, y, z) ; writes("------*N")
$)    

// Print 3 values given printing function
and print3(printfn, x, y, z) be
$(  writes("X = ") ; printfn(x) ; wrch('*N')
    writes("Y = ") ; printfn(y) ; wrch('*N')
    writes("Z = ") ; printfn(z) ; wrch('*N')
$)
Output:
X = 7444
Y = -12
Z = 0

X = -12
Y = 0
Z = 7444
------
X = lions, tigers, and
Y = bears, oh my!
Z = (from the "Wizard of OZ")

X = (from the "Wizard of OZ")
Y = bears, oh my!
Z = lions, tigers, and
------

C

Although C does not have a generic catch-all variable type, strings or arrays of characters can be used ( or misused ) to simulate the effect. Strings are often used to process arbitrarily large or small numbers which can't be represented by the C Standard Library. Strings are thus used for this task to accept whatever the user enters. Each entry is treated as a string and is scanned. If any one of them contains a single 'non-number' character, then the whole set is treated as a set of strings.

The first implementation is generic and can be used for any entries ( integer, floating point, strings). The second one is specific to the task and only sorts integers.

Generic Implementation

#include<string.h>
#include<stdlib.h>
#include<stdio.h>

#define MAX 3

int main()
{
  char values[MAX][100],tempStr[100];
  int i,j,isString=0;
  double val[MAX],temp;
  
  for(i=0;i<MAX;i++){
    printf("Enter %d%s value : ",i+1,(i==0)?"st":((i==1)?"nd":"rd"));
    fgets(values[i],100,stdin);
    
    for(j=0;values[i][j]!=00;j++){
      if(((values[i][j]<'0' || values[i][j]>'9') && (values[i][j]!='.' ||values[i][j]!='-'||values[i][j]!='+'))
      ||((values[i][j]=='.' ||values[i][j]=='-'||values[i][j]=='+')&&(values[i][j+1]<'0' || values[i][j+1]>'9')))
        isString = 1;
    }
  }
  
  if(isString==0){
    for(i=0;i<MAX;i++)
      val[i] = atof(values[i]);
  }
  
  for(i=0;i<MAX-1;i++){
    for(j=i+1;j<MAX;j++){
      if(isString==0 && val[i]>val[j]){
        temp = val[j];
        val[j] = val[i];
        val[i] = temp;
      }
        
      else if(values[i][0]>values[j][0]){
        strcpy(tempStr,values[j]);
        strcpy(values[j],values[i]);
        strcpy(values[i],tempStr);
      }
    }
  }
  
  for(i=0;i<MAX;i++)
    isString==1?printf("%c = %s",'X'+i,values[i]):printf("%c = %lf",'X'+i,val[i]);
  
  return 0;
}
The output shows three test cases, two as specified in the task, and one which mixes numbers and strings. The output is sorted considering all of them as strings in that case.
Enter 1st value : 77444
Enter 2nd value : -12
Enter 3rd value : 0
X = -12
Y = 0
Z = 77444

Enter 1st value : lions, tigers, and
Enter 2nd value : bears, oh my!
Enter 3rd value : (from the "Wizard of OZ")
X = (from the "Wizard of OZ")
Y = bears, oh my!
Z = lions, tigers, and

Enter 1st value : -12
Enter 2nd value : bears, oh my!
Enter 3rd value : 77444
X = -12
Y = 77444
Z = bears, oh my!

Task Specific Implementation

#include<stdio.h>

int main()
{
  int x = 77444,y=-12,z=0,temp;
  
  printf("Before sorting :\nx = %d\ny = %d\nz = %d",x,y,z);
  
  do{
  temp = x;
  
  if(temp > y){
    x = y;
    y = temp;
  }
  
  if(z < y){
    temp = y;
    y = z;
    z = temp;
  }
  }while(x>y || y>z);
  
  printf("\nAfter sorting :\nx = %d\ny = %d\nz = %d",x,y,z);
  
  return 0;
}

Output :

Before sorting :
x = 77444
y = -12
z = 0
After sorting :
x = -12
y = 0
z = 77444

C#

Works with: C sharp version 7.0
using System;
public class Program
{
    public static void Main()
    {
        (int x, int y, int z) = (77444, -12, 0);

        //Sort directly:
        if (x > y) (x, y) = (y, x);
        if (x > z) (x, z) = (z, x);
        if (y > z) (y, z) = (z, y);
        Console.WriteLine((x, y, z));

        var (a, b, c) = (
            "lions, tigers, and",
            "bears, oh my!",
            "(from the 'Wizard of OZ')");
        
        //Sort with generic method:
        Sort(ref a, ref b, ref c);
        Console.WriteLine((a, b, c));
    }
    
    public static void Sort<T>(ref T a, ref T b, ref T c)
        where T : IComparable<T>
    {
        if (a.CompareTo(b) > 0) (a, b) = (b, a);
        if (a.CompareTo(c) > 0) (a, c) = (c, a);
        if (b.CompareTo(c) > 0) (b, c) = (c, b);
    }
}
Output:
(-12, 0, 77444)
((from the 'Wizard of OZ'), bears, oh my!, lions, tigers, and)

C++

#include <algorithm>
#include <iostream>
#include <string>
#include <vector>
 
template < class T >
void sort3( T& x, T& y, T& z) {
    std::vector<T> v{x, y, z};
    std::sort(v.begin(), v.end());
    x = v[0]; y = v[1]; z = v[2];
}
int main() {
    int xi = 77444, yi = -12, zi = 0;
    sort3( xi, yi, zi );
    std::cout << xi << "\n" << yi << "\n" << zi << "\n\n";
 
    std::string xs, ys, zs;
    xs = "lions, tigers, and";
    ys = "bears, oh my!";
    zs = "(from the \"Wizard of OZ\")";
    sort3( xs, ys, zs );
    std::cout << xs << "\n" << ys << "\n" << zs << "\n\n";
 
    float xf = 11.3f, yf = -9.7f, zf = 11.17f;
    sort3( xf, yf, zf );
    std::cout << xf << "\n" << yf << "\n" << zf << "\n\n";
}
Output:
-12
0
77444

(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and

-9.7
11.17
11.3

CLU

% Sort three variables.
% The variables must all be of the same type, and the type
% must implement the less-than comparator.
sort_three = proc [T: type] (x,y,z: T) returns (T,T,T)
             where T has lt: proctype (T,T) returns (bool)
    if y<x then x,y := y,x end
    if z<y then y,z := z,y end
    if y<x then x,y := y,z end
    return(x,y,z)
end sort_three

% Test it out on three values, when also given a type and a
% formatter.
example = proc [T: type] (x,y,z: T, fmt: proctype (T) returns (string))
          where T has lt: proctype (T,T) returns (bool)
    po: stream := stream$primary_output()
    
    % Print the variables
    stream$putl(po, "x=" || fmt(x) 
                || " y=" || fmt(y)
                || " z=" || fmt(z))
     
    % Sort them 
    x,y,z := sort_three[T](x,y,z)
    
    % Print them again
    stream$putl(po, "x=" || fmt(x) 
                || " y=" || fmt(y)
                || " z=" || fmt(z)
                || "\n")
end example     

% And then we also need formatters, since those are not standardized
% such as '<' is.
fmt_real = proc (n: real) returns (string)
    return(f_form(n,2,2))
end fmt_real

fmt_str = proc (s: string) returns (string)
    return( "'" || s || "'" )
end fmt_str

% Test it out on values of each type
start_up = proc ()
    example[int] (77444, -12, 0, int$unparse)
    example[real] (11.3, -9.7, 11.17, fmt_real)
    example[string] ("lions, tigers and", "bears, oh my!",
                    "(from the \"Wizard of Oz\")", fmt_str)
end start_up
Output:
x=77444 y=-12 z=0
x=-12 y=0 z=77444

x=11.30 y=-9.70 z=11.17
x=-9.70 y=11.17 z=11.30

x='lions, tigers and' y='bears, oh my!' z='(from the "Wizard of Oz")'
x='(from the "Wizard of Oz")' y='lions, tigers and' z='lions, tigers and'

COBOL

       program-id. 3var.
       data division.
       working-storage section.
       1 n binary pic 9(4).
       1 num pic -(7)9.
       1 a1 pic x(32) value "lions, tigers, and".
       1 a2 pic x(32) value "bears, oh my!".
       1 a3 pic x(32) value "(from the ""Wizard of OZ"")".
       1 n1 pic x(8) value "77444".
       1 n2 pic x(8) value "-12".
       1 n3 pic x(8) value "0".
       1 alpha-table.
        2 alpha-entry occurs 3 pic x(32).
       1 numeric-table.
        2 numeric-entry occurs 3 pic s9(8).
       1 filler value "x = y = z = ".
        2 lead-in occurs 3 pic x(4).
       procedure division.
       begin.
           move a1 to alpha-entry (1)
           move a2 to alpha-entry (2)
           move a3 to alpha-entry (3)
           sort alpha-entry ascending alpha-entry
           perform varying n from 1 by 1
           until n > 3
               display lead-in (n) alpha-entry (n)
           end-perform

           display space

           compute numeric-entry (1) = function numval (n1)
           compute numeric-entry (2) = function numval (n2)
           compute numeric-entry (3) = function numval (n3)
           sort numeric-entry ascending numeric-entry
           perform varying n from 1 by 1
           until n > 3
               move numeric-entry (n) to num
               display lead-in (n) num
           end-perform

           stop run
           .
       end program 3var.
Output:
x = (from the "Wizard of OZ")
y = bears, oh my!
z = lions, tigers, and

x =      -12
y =        0
z =    77444

Cowgol

include "cowgol.coh";

# Sort 3 values
sub sort3(a: int32, b: int32, c: int32): (x: int32, y: int32, z: int32) is
    sub sort2(a: int32, b: int32): (x: int32, y: int32) is  
        if a > b then
            x := b;
            y := a;
        else
            x := a;
            y := b;
        end if;
    end sub;
    
    x := a;
    y := b;
    z := c;
    (x, y) := sort2(x, y);
    (x, z) := sort2(x, z);
    (y, z) := sort2(y, z);
end sub;

# Print 3 values
sub print3(a: int32, b: int32, c: int32) is
    sub print1(a: int32) is
        var buf: uint8[10];
        [IToA(a, 10, &buf[0])] := 0;
        print(&buf[0]);
        print_char(' ');
    end sub;
    
    print1(a);
    print1(b);
    print1(c);
    print_nl();
end sub;
    
var x: int32 := 77444;
var y: int32 := -12;
var z: int32 := 0;

# Print 3 values before sorting
print3(x, y, z);

# Sort 3 values
(x, y, z) := sort3(x, y, z);

# Print 3 values after sorting
print3(x, y, z);
Output:
77444 -12 0
-12 0 77444

D

import std.stdio;

void main() {
    driver(77444, -12, 0);
    driver("lions, tigers, and", "bears, oh my!", "(from the \"Wizard of OZ\")");
}

void driver(T)(T x, T y, T z) {
    writeln("BEFORE: x=[", x, "]; y=[", y, "]; z=[", z, "]");
    sort3Var(x,y,z);
    writeln("AFTER: x=[", x, "]; y=[", y, "]; z=[", z, "]");
}

void sort3Var(T)(ref T x, ref T y, ref T z)
out {
    assert(x<=y);
    assert(x<=z);
    assert(y<=z);
}
body {
    import std.algorithm : swap;

    if (x < y) {
        if (z < x) {
            swap(x,z);
        }
    } else if (y < z) {
        swap(x,y);
    } else {
        swap(x,z);
    }
    if (z<y) {
        swap(y,z);
    }
}
Output:
BEFORE: x=[77444]; y=[-12]; z=[0]
AFTER: x=[-12]; y=[0]; z=[77444]
BEFORE: x=[lions, tigers, and]; y=[bears, oh my!]; z=[(from the "Wizard of OZ")]
AFTER: x=[(from the "Wizard of OZ")]; y=[bears, oh my!]; z=[lions, tigers, and]

EasyLang

proc sort3 . a b c .
   if a > c
      swap a c
   .
   if b > c
      swap b c
   .
   if a > b
      swap a b
   .
.
x = 77444
y = -12
z = 0
sort3 x y z
print x & " " & y & " " & z
# 
proc sort3str . a$ b$ c$ .
   if strcmp a$ c$ > 0
      swap a$ c$
   .
   if strcmp b$ c$ > 0
      swap b$ c$
   .
   if strcmp a$ b$ > 0
      swap a$ b$
   .
.
x$ = "lions, tigers, and"
y$ = "bears, oh my!"
z$ = "(from the \"Wizard of OZ\")"
sort3str x$ y$ z$
print x$
print y$
print z$


EDSAC order code

[Sort three variables, for Rosetta Code.
 EDSAC, Initial Orders 2]
[---------------------------------------------------------------------------
 Sorts three 35-bit variables x, y, x, stored at 0#V, 2#V, 4#V respectively.
 Uses the algortihm:
    if x > z then swap( x,z)
    if y > z then swap( y,z)
    if x > y then swap( x,y)
 At most two swaps are carried out in any particular case.
 ----------------------------------------------------------------------------]
[Arrange the storage]
            T47K P96F  [M parameter: main routine]
            T55K P128F [V parameter: variables to be sorted]

[Compressed form of library subroutine R2.
 Reads integers at load time and is then overwritten.]
            GKT20FVDL8FA40DUDTFI40FA40FS39FG@S2FG23FA5@T5@E4@E13Z
            T#V     [tell R2 where to store integers]
[EDIT: List of 35-bit integers separated by 'F', list terminated by '#TZ'.]
987654321F500000000F123456789#TZ

[Main routine]
            E25K TM GK
      [0]   A4#V S#V  [accumulator := z - x]
            E8@       [skip the swap if x <= z]
            TD        [0D := z - x]
            A#V U4#V  [z := x]
            AD        [acc := old z]
            T#V       [x := old z]
      [8]   TF        [clear acc]
            A4#V S2#V [acc := z - y]
            E17@      [skip the swap if y <= z]
            TD        [0D := z - y]
            A2#V U4#V [z := y]
            AD        [acc := old z]
            T2#V      [y := old z]
     [17]   TF        [clear acc]
            A2#V S#V  [acc := y - x]
            E26@      [skip the swap if x <= y]
            TD        [0D := y - x]
            A#V U2#V  [y := x]
            AD        [acc := old y]
            T#V       [x := old y]
     [26]   ZF        [halt the machine]
            EZ        [define entry point]
            PF        [acc = 0 on entry]
[end]

Elena

ELENA 6.x :

import extensions;
 
sortThree(ref object a, ref object b, ref object c)
{
    if (a > b) { exchange(ref a, ref b) };
    if (a > c) { exchange(ref a, ref c) };
    if (b > c) { exchange(ref b, ref c) }
}

public program()
{
    var x := 5;
    var y := 1;
    var z := 2;
 
    var a := "lions, tigers, and";
    var b := "bears, oh my!";
    var c := "(from the 'Wizard of OZ')";
 
    sortThree(ref x,ref y,ref z);
    sortThree(ref a,ref b,ref c);
 
    console.printLine(x,",",y,",",z);
    console.printLine(a,",",b,",",c)
}
Output:
1,2,5
(from the 'Wizard of OZ'),bears, oh my!,lions, tigers, and

Elixir

x = 'lions, tigers, and'
y = 'bears, oh my!'
z = '(from the "Wizard of OZ")'

[x, y, z] = Enum.sort([x, y, z])
IO.puts "x = #{x}\ny = #{y}\nz = #{z}\n"
 
x = 77444
y = -12
z = 0

[x, y, z] = Enum.sort([x, y, z])
IO.puts "x = #{x}\ny = #{y}\nz = #{z}"
Output:
x = (from the "Wizard of OZ")
y = bears, oh my!
z = lions, tigers, and

x = -12
y = 0
z = 77444

F#

 let x = "lions, tigers, and"
 let y = "bears, oh my!"
 let z = """(from the "Wizard of OZ")"""
 List.iter (printfn "%s") (List.sort [x;y;z])
Output:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and

Factor

USING: arrays io kernel prettyprint sequences sorting ;
IN: rosetta-code.sort-three

: sort3 ( b c a -- a b c ) 3array natural-sort first3 ;

"lions, tigers, and"
"bears, oh my!"
"(from the \"Wizard of OZ\")"
sort3 [ print ] tri@

77444 -12 0 sort3 [ . ] tri@
Output:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and
-12
0
77444

FALSE

FALSE supports neither floating point numbers nor strings.

{ [s]waps two variables. (varref; varref) → () }
[
  b:  { loads the value at the top of the stack into b }
  a:  { loads the value at the top of the stack into a }

  a;; t:  { loads the value stored in the variable stored in a (hence the double dereference) into t }
  b;; a;:  { loads the value stored in the variable stored in b into the variable stored in a }
  t; b;:  { loads the value stored in t into the variable stored in b }
]s:

{ [p]rints the three variables. }
[
  "X = " x;. 10,
  "Y = " y;. 10,
  "Z = " z;. 10,
]p:

77444 x:
12_ y:
0 z:

p;!

{ if x > y, swap x and y }
x;y;> [xys;!] ?

{ if y > z, swap y and z }
y;z;> [yzs;!] ?

{ if x > y, swap x and y }
x;y;> [xys;!] ?

"After sorting:
"

p;!
Output:
X = 77444
Y = -12
Z = 0
After sorting:
X = -12
Y = 0
Z = 77444

FreeBASIC

Shows the use of macros, which are type-agnostic (though you cannot mix string and numerical types).

#macro sort_three( x, y, z )
    if x>y then swap x, y
    if y>z then swap y, z
    if x>y then swap x, y
#endmacro

'demonstrate this for strings
dim as string x =  "lions, tigers, and"
dim as string y =  "bears, oh my!"
dim as string z =  "(from the ""Wizard of OZ"")"

sort_three(x,y,z)
print x
print y
print z : print


'demonstrate this for signed integers
dim as integer a = 77444
dim as integer b = -12
dim as integer c = 0

sort_three(a,b,c)
print a
print b
print c
Output:
(from the "Wizard of OZ")

bears, oh my! lions, tigers, and

-12

0
77444

Forth

Integers

In GNU Forth the machine's integers are the default data type. It is straightforward to sort these on the Forth Data Stack.
Note: Assigning the values to variables is simple however unless storage in variables was needed to retain the values, they would typically be used directly from the stack by a subsequent operation in the program.

\ sort 3 integers
VARIABLE X  VARIABLE Y   VARIABLE Z

: VARS@  ( --- n n n)  X @  Y @   Z @ ; \ read variables
: VARS!  ( n n n -- )  Z !  Y !   X ! ; \ store variables

: ?SWAP     ( a b -- a b)   \ conditional swap
            2DUP < IF SWAP THEN ;

: SORT3INTS ( a b c -- c b a)  ?SWAP >R  ?SWAP  R>  ?SWAP ;

Testing is done using the Forth console using '?' to view VARIABLE contents

 ok
77000 -12 0 VARS!  ok
X ? 77000  ok
Y ? -12  ok
Z ? 0  ok
VARS@ SORT3INTS VARS!  ok
X ? 77000  ok
Y ? 0  ok
Z ? -12  ok

Strings

Strings require extending the language but the primitives needed are part of ANS/ISO Forth.

DECIMAL
: BUFFER: ( n -- ) CREATE ALLOT ;

64 BUFFER: X
64 BUFFER: Y
64 BUFFER: Z

: S'  ( <text> )  [CHAR] ' PARSE ;

S' (from the "Wizard of OZ")' X PLACE
S' bears, oh my!'             Y PLACE
S' lions, tigers, and'        Z PLACE

\ counted string compare less than
: <S        ( caddr caddr -- caddr caddr flag)
            COUNT ROT COUNT COMPARE 1 = ;

: ?SWAPSTR  ( caddr caddr -- caddr caddr)  \ conditional string swap
             2DUP <S IF SWAP THEN ;

\ sort on stack as done for integers
: SORT3STRINGS   ?SWAPSTR >R  ?SWAPSTR R> ?SWAPSTR ;

\ non-destructive print 3 counted-strings from data stack
: .STRS  ( caddr1 caddr2 caddr3 -- caddr1 caddr2 caddr3) \ order is dependant
           3 0 DO ROT  DUP CR COUNT TYPE  LOOP ;

With these extensions we can do the same testing at the Forth console and examine the string order with '.STRS'.

 ok
X Y Z  ok
.S <3> 2142061672 2142061760 2142061848  ok
.STRS
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and ok
SORT3STRINGS  ok
.S <3> 2142061848 2142061760 2142061672  ok
.STRS
lions, tigers, and
bears, oh my!
(from the "Wizard of OZ") ok

Fortran

Fortran does not offer a multi-mode facility whereby a variable can be the union of various basic types such as integer or floating-point or character. The EQUIVALENCE statement can cause three such different variables to be placed at the same storage location or indeed, because parameter type-checking is rarely performed by a Fortran compiler (especially with routines compiled separately) it is often possible to pass a floating-point variable to a subroutine expecting an integer, and so forth. Leaving aside questions of storage size mismatch (as when a subroutine stores a sixty-four bit double-precision value into a parameter it had been supplied as a sixteen-bit integer, say) the bit patterns of disparate types will rarely involve a useful ordering. For example, an eight-byte floating-point variable could contain the bit pattern of "Hi There" but the numerical value that will manifest will not likely be useful in sorting text. Though it could be. Imagine having a collection of eight-character codes that is to be searched frequently by a binary chop method. If the actual ordering is unimportant, they could be both sorted and searched as REAL*8 variables, dealing with all eight characters at one blow. However, given the modern floating-point usage of Not-a-Number and the like, it would probably be safer to work with integer variables so that every bit pattern would be distinct. Alas, on the B6700, the high-order bit of its 48-bit word was not used in arithmetic so if an eight-bit character code were to be placed in the high-order eight bits, some character codes would not be distinguished.

It is possible to use floating-point variables to store integer values and their ordering will be sensible, but the bit patterns of integer and floating-point values are usually very different. Again, a subroutine that is supplied integer variables (even of the right size) but which works with floating-point variables (or vice-versa) will not produce a sensible ordering. Except perhaps on a B6700 where integer values were represented as floating-point numbers with no fractional part. Operations such as add, subtract, and multiply proceeded as normal while divide discarded any resulting fractional part.

The most flexible type of variable is text, as the text can represent any type of value - but as text, not as a proper number. The ordering resulting from numbers represented as text will be very dependent on their format. This is discussed in Natural_sorting for example.

The example source uses F90 mainly to enable the contained routine SWAPC though it could be made into a separate subroutine. Further F90 facilities would allow the definition of a "generic" SORT3 routine, with a lot of syntax that would enable a SORT3I2, SORT3I4, SORT3F4, etc. routines for INTEGER*2, INTEGER*4, REAL*4, etc. to be selected for each case. A suitable pre-processor scheme could perhaps generate these variations, but alas, it is not standard. The resulting SORT3 routine could be invoked for sets of parameters of any of the types prepared for, but it will only appear to be one routine working with different types of parameters; in fact different actual routines would be invoked by the compiler selecting according to the type of the actual parameters.

There would be similar requirements for a SWAP routine for each type of parameter, for alas, Fortran does not define a SWAP statement. The temporary variable needed for the SWAP process is defined rather intimidatingly as having the size of the largest of the three parameters; prior to F90 variables defined in a routine could only have a size defined at compile time, which would have to be "surely big enough". Rather than have this redefined for each invocation of SWAPC (where it would be the larger of the two parameters) it is defined once in SORT3. However, all three parameters should be the same size, or risk truncation. Using a great deal more syntax (or, as standardised in F2003) it is possible to have character variables be resized on each assignment to them to accommodate the length of text being assigned.

One could make rather more use of the facilities of F90 and define a compound data type, such as
      TYPE(MONGREL)
       INTEGER TYPEIS
       INTEGER VI
       REAL VF
       CHARACTER*(enuff) VC
       ...etc...
      END TYPE MONGREL
      TYPE (MONGREL) DOG

So that DOG.TYPEIS would indicate which component to access. Still further ploys would enable storage to be allocated only for the type currently in use, especially for CHARACTER variables, and via a great deal more syntax defining how to perform operations such as .GT. and the like, MONGREL type variables can be used in expressions involving such operators just as can variables of the basic types. This sort of approach is demonstrated in Arithmetic/Rational#Fortran, but otherwise, every reference to a MONGREL will involve some sort of CASE statement to select the appropriate usage, hopefully of related types only. Serious computation with such MONGREL variables surely will not be speedy and thus would be un-Fortrannish. What to do when a text string meets a complex number remains obscure - convert the number to a text (but, what format?), does the text represent a number? And what type results from such miscegnation?

Routines that modify their parameters should not be invoked with constants (or text literals) as such parameters... Some systems allow constants to be in protected storage, and if so, an attempt to modify such storage will produce a run-time error. Otherwise, it all depends on how constants are passed as parameters. If a temporary storage item is loaded with the desired value and the address of that scratch variable is passed, then disaster will be averted - though good results may not be produced.

For convenience in setting up the two examples, an array is used to hold the test data. The subroutine is not invoked with an array parameter, it is invoked with three separate elements of the array. The DATA statement initialising the array looks to be the transpose of the desired ordering, because of the way Fortran orders elements in storage.
      SUBROUTINE SORT3(X,Y,Z) !Perpetrate a bubblesort in-line.
       CHARACTER*(*) X,Y,Z  !Just three to rearrange.
       CHARACTER*(MAX(LEN(X),LEN(Y),LEN(Z))) T  !Really, they should all be the same length.
        IF (X.GT.Y) CALL SWAPC(X,Y) !The first pass: for i:=2:3 do if a(i - 1) > a(i) swap
        IF (Y.GT.Z) CALL SWAPC(Y,Z) !The second test of the first pass.
        IF (X.GT.Y) CALL SWAPC(X,Y) !The second pass: for i:=2:2...
       CONTAINS   !Alas, Fortran does not offer a SWAP statement.
        SUBROUTINE SWAPC(A,B) !So, one must be devised for each case.
        CHARACTER*(*) A,B !To have their content swapped.
         T = A      !Ccpy the first to a safe space.
         A = B      !Copy the second on to the first.
         B = T      !Copy what had been first to the second.
        END SUBROUTINE SWAPC  !One of these will be needed for each type of datum.
       END SUBROUTINE SORT3 !No attempt is made to stop early, as for already-ordered data.

       PROGRAM POKE
       CHARACTER*28 XYZ(3,2)  !Encompass the two examples.
       DATA XYZ/    !Storage order is "column-major".
     1 'lions, tigers, and','bears, oh my!','(from the "Wizard of OZ")',  !So (1,1), (2,1), (3,1)
     2 '77444','  -12','    0'/ !So this looks like a transposed array. But     (1,2), (2,2), (3,2) 
       INTEGER I    !A stepper for the loop.
       DO I = 1,2   !Two examples.
         WRITE (6,66) "Supplied: ", XYZ(1:3,I)  !As given.
   66    FORMAT (A12,3(" >",A,"<"))   !Show as >text< for clarity.

         CALL SORT3(XYZ(1,I),XYZ(2,I),XYZ(3,I)) !Three separate variables, that happen to be in an array.

         WRITE (6,66) "Sorted, ? ", XYZ(1:3,I)  !The result.
       END DO     !On to the next example.
       END  !Nothing much.

Output: the texts showing numbers appear in text order, not the order of their numbers. Incidentally, not everything is done in ASCII. The EBCDIC ordering is different.

  Supplied:  >lions, tigers, and          < >bears, oh my!               < >(from the "Wizard of OZ")   <
  Sorted, ?  >(from the "Wizard of OZ")   < >bears, oh my!               < >lions, tigers, and          <
  Supplied:  >77444                       < >  -12                       < >    0                       <
  Sorted, ?  >    0                       < >  -12                       < >77444                       <

Fōrmulæ

Fōrmulæ programs are not textual, visualization/edition of programs is done showing/manipulating structures but not text. Moreover, there can be multiple visual representations of the same program. Even though it is possible to have textual representation —i.e. XML, JSON— they are intended for storage and transfer purposes more than visualization and edition.

Programs in Fōrmulæ are created/edited online in its website.

In this page you can see and run the program(s) related to this task and their results. You can also change either the programs or the parameters they are called with, for experimentation, but remember that these programs were created with the main purpose of showing a clear solution of the task, and they generally lack any kind of validation.

Solution

Test case 1

File:Fōrmulæ - Sort three variables 01.png

File:Fōrmulæ - Sort three variables 02.png

Test case 2

File:Fōrmulæ - Sort three variables 03.png

File:Fōrmulæ - Sort three variables 04.png

Free Pascal

The FPC (FreePascal Compiler) adopted Delphi’s generics scheme. It works in the {$mode objFPC} and {$mode Delphi} compiler compatibility modes, the former requiring the keywords generic/specialize.

{$mode objFPC}

generic procedure sort<T>(var X, Y: T);
	procedure swap;
	var
		Z: T;
	begin
		Z := X;
		X := Y;
		Y := Z
	end;
begin
	if X > Y then
	begin
		swap
	end
end;

generic procedure sort<T>(var X, Y, Z: T);
begin
	specialize sort<T>(X, Y);
	specialize sort<T>(X, Z);
	specialize sort<T>(Y, Z)
end;

generic procedure print<T>(const X, Y, Z: T);
begin
	writeLn('X = ', X);
	writeLn('Y = ', Y);
	writeLn('Z = ', Z)
end;

{ === MAIN ============================================================= }
var
	A, B, C: string;
	I, J, K: integer;
	P, Q, R: real;
begin
	A := 'lions, tigers, and';
	B := 'bears, oh my!';
	C := '(from the "Wizard of OZ")';
	
	specialize sort<string>(A, B, C);
	specialize print<string>(A, B, C);
	
	writeLn;
	I := 77444;
	J :=   -12;
	K :=     0;
	specialize sort<integer>(I, J, K);
	specialize print<integer>(I, J, K);
	
	writeLn;
	P :=  12.34;
	Q := -56.78;
	R :=   9.01;
	specialize sort<real>(P, Q, R);
	specialize print<real>(P, Q, R)
end.
Output:
X = (from the "Wizard of OZ")
Y = bears, oh my!
Z = lions, tigers, and

X = -12
Y = 0
Z = 77444

X = -5.6780000000000001E+001
Y =  9.0099999999999998E+000
Z =  1.2340000000000000E+001

Frink

The following sorts the values in the variables x, y, and z and sets the sorted values back to the variables.

x = 77444
y = -12
z = 0

[x,y,z] = sort[[x,y,z]]
println["x = $x"]
println["y = $y"]
println["z = $z"]
Output:
x = -12
y = 0
z = 77444

Go

There are ways of doing this task in a generic way in Go but they are a bit cumbersome and it would not be idiomatic. Shown here then are solutions coded specifically to the string and integer types of the task test cases. Solutions would be very similar for any of the other comparable Go types such as float64.

package main

import (
    "fmt"
    "log"
    "sort"
)

var (
    stringsIn = []string{
        `lions, tigers, and`,
        `bears, oh my!`,
        `(from the "Wizard of OZ")`}
    intsIn = []int{77444, -12, 0}
)

func main() {
    {
        // initialize three vars
        x, y, z := stringsIn[0], stringsIn[1], stringsIn[2]

        // I. Task suggested technique, move values to array (slice).
        // It's consise and relies on library code.
        s := []string{x, y, z}
        sort.Strings(s)
        x, y, z = s[0], s[1], s[2]

        // validate
        if x > y || y > z {
            log.Fatal()
        }

        // II. Likely fastest technique, minimizing tests and data movement.
        // Least consise though, hardest to understand, and most chance to make
        // a coding mistake.
        x, y, z = stringsIn[0], stringsIn[1], stringsIn[2] // (initialize)
        if x < y {
            switch {
            case y < z:
            case x < z:
                y, z = z, y
            default:
                x, y, z = z, x, y
            }
        } else {
            switch {
            case x < z:
                x, y = y, x
            case z < y:
                x, z = z, x
            default:
                x, y, z = y, z, x
            }
        }
        if x > y || y > z { // (validate)
            log.Fatal()
        }

        // III.  A little more consise than II, easier to understand, almost
        // as fast.
        x, y, z = stringsIn[0], stringsIn[1], stringsIn[2] // (initialize)
        if x > y {
            x, y = y, x
        }
        if y > z {
            y, z = z, y
        }
        if x > y {
            x, y = y, x
        }
        if x > y || y > z { // (validate)
            log.Fatal()
        }
        fmt.Println("sorted strings:")
        fmt.Println(" ", x)
        fmt.Println(" ", y)
        fmt.Println(" ", z)
        fmt.Println("original data:")
        fmt.Println(" ", stringsIn[0])
        fmt.Println(" ", stringsIn[1])
        fmt.Println(" ", stringsIn[2])
    }
    // same techniques, with integer test case
    {
        // task suggested technique
        x, y, z := intsIn[0], intsIn[1], intsIn[2] // (initialize)
        s := []int{x, y, z}
        sort.Ints(s)
        x, y, z = s[0], s[1], s[2]
        if x > y || y > z { // (validate)
            log.Fatal()
        }

        // minimizing data movement
        x, y, z = intsIn[0], intsIn[1], intsIn[2] // (initialize)
        if x < y {
            switch {
            case y < z:
            case x < z:
                y, z = z, y
            default:
                x, y, z = z, x, y
            }
        } else {
            switch {
            case x < z:
                x, y = y, x
            case z < y:
                x, z = z, x
            default:
                x, y, z = y, z, x
            }
        }
        if x > y || y > z { // (validate)
            log.Fatal()
        }

        // three swaps
        x, y, z = intsIn[0], intsIn[1], intsIn[2] // (initialize)
        if x > y {
            x, y = y, x
        }
        if y > z {
            y, z = z, y
        }
        if x > y {
            x, y = y, x
        }
        if x > y || y > z { // (validate)
            log.Fatal()
        }
        fmt.Println("sorted ints:", x, y, z)
        fmt.Println("original data:", intsIn)
    }
    // To put any of these techniques in a function, a function could just
    // take three values and return them sorted.
    {
        sort3 := func(x, y, z int) (int, int, int) {
            if x > y {
                x, y = y, x
            }
            if y > z {
                y, z = z, y
            }
            if x > y {
                x, y = y, x
            }
            return x, y, z
        }
        x, y, z := intsIn[0], intsIn[1], intsIn[2] // (initialize)
        x, y, z = sort3(x, y, z)
        if x > y || y > z { // (validate)
            log.Fatal()
        }
    }
    // Alternatively, a function could take pointers
    {
        sort3 := func(x, y, z *int) {
            if *x > *y {
                *x, *y = *y, *x
            }
            if *y > *z {
                *y, *z = *z, *y
            }
            if *x > *y {
                *x, *y = *y, *x
            }
        }
        x, y, z := intsIn[0], intsIn[1], intsIn[2] // (initialize)
        sort3(&x, &y, &z)
        if x > y || y > z { // (validate)
            log.Fatal()
        }
    }
}
Output:
sorted strings:
  (from the "Wizard of OZ")
  bears, oh my!
  lions, tigers, and
original data:
  lions, tigers, and
  bears, oh my!
  (from the "Wizard of OZ")
sorted ints: -12 0 77444
original data: [77444 -12 0]

Haskell

Fortunately, Haskell prevents us from doing this kind of thing. It does makes flexible use of bound names, including names for function arguments, but it also protects us from the heavy costs to productivity and reliability that are inevitably imposed by mutating the meaning of bound names at run-time.

Although mutation is not on the menu, parameterised types do allow us to define polymorphic functions which can, for example, be applied both to lists of strings and also to lists of integers or lists of floats. The following functions work with triples of any type for which the <= or compare functions are defined – in other words, any type for which an instance of the Ord class is defined.

import Data.List (sort)

sortedTriple
  :: Ord a
  => (a, a, a) -> (a, a, a)
sortedTriple (x, y, z) =
  let [a, b, c] = sort [x, y, z]
  in (a, b, c)

sortedListfromTriple
  :: Ord a
  => (a, a, a) -> [a]
sortedListfromTriple (x, y, z) = sort [x, y, z]

-- TEST ----------------------------------------------------------------------
main :: IO ()
main = do
  print $
    sortedTriple
      ("lions, tigers, and", "bears, oh my!", "(from the \"Wizard of OZ\")")
  print $
    sortedListfromTriple
      ("lions, tigers, and", "bears, oh my!", "(from the \"Wizard of OZ\")")
  print $ sortedTriple (77444, -12, 0)
  print $ sortedListfromTriple (77444, -12, 0)
Output:
("(from the \"Wizard of OZ\")","bears, oh my!","lions, tigers, and")
["(from the \"Wizard of OZ\")","bears, oh my!","lions, tigers, and"]
(-12,0,77444)
[-12,0,77444]

IS-BASIC

100 LET X=77444:LET Y=-12:LET Z=0
110 PRINT X;Y;Z
120 CALL SHORT(X,Y,Z)
130 PRINT X;Y;Z
140 DEF SHORT(REF A,REF B,REF C)
150   IF A>B THEN LET T=A:LET A=B:LET B=T
160   IF B>C THEN LET T=B:LET B=C:LET C=T
170   IF A>B THEN LET T=A:LET A=B:LET B=T
180 END DEF
Output:
 77444 -12  0
-12  0  77444

J

Note that this is extremely bad form, and you will stumble over why it is bad form if you try using it in any useful implementation:

   x =:  'lions, tigers, and'
   y =:  'bears, oh my!'
   z =:  '(from the "Wizard of OZ")'
   'x y z'=: /:~".'x;y;<z'
   x
(from the "Wizard of OZ")
   y
bears, oh my!
   z
lions, tigers, and
   
   x =:  77444
   y =:    -12
   z =:      0
   'x y z'=: /:~".'x;y;<z'
   x
_12
   y
0
   z
77444

Java

import java.util.Comparator;
import java.util.stream.Stream;

class Box {
    public int weightKg;

    Box(final int weightKg) {
        this.weightKg = weightKg;
    }
}

public class Sort3Vars {
    public static void main(String... args) {
        int iA = 21;
        int iB = 11;
        int iC = 82;
        int[] sortedInt = Stream.of(iA, iB, iC).sorted().mapToInt(Integer::intValue).toArray();
        iA = sortedInt[0];
        iB = sortedInt[1];
        iC = sortedInt[2];
        System.out.printf("Sorted values: %d %d %d%n", iA, iB, iC);

        String sA = "s21";
        String sB = "s11";
        String sC = "s82";
        Object[] sortedStr = Stream.of(sA, sB, sC).sorted().toArray();
        sA = (String) sortedStr[0];
        sB = (String) sortedStr[1];
        sC = (String) sortedStr[2];
        System.out.printf("Sorted values: %s %s %s%n", sA, sB, sC);

        Box bA = new Box(200);
        Box bB = new Box(12);
        Box bC = new Box(143);
        // Provides a comparator for Box instances
        Object[] sortedBox = Stream.of(bA, bB, bC).sorted(Comparator.comparingInt(a -> a.weightKg)).toArray();
        bA = (Box) sortedBox[0];
        bB = (Box) sortedBox[1];
        bC = (Box) sortedBox[2];
        System.out.printf("Sorted Boxes: %dKg %dKg %dKg%n", bA.weightKg, bB.weightKg, bC.weightKg);
    }
}
Output:
Sorted values: 11 21 82
Sorted values: s11 s21 s82
Sorted Boxes: 12Kg 143Kg 200Kg

JavaScript

const printThree = (note, [a, b, c], [a1, b1, c1]) => {
  console.log(`${note}
    ${a} is: ${a1}
    ${b} is: ${b1}
    ${c} is: ${c1}
  `);
};
const sortThree = () => {

  let a = 'lions, tigers, and';
  let b = 'bears, oh my!';
  let c = '(from the "Wizard of OZ")';
  printThree('Before Sorting', ['a', 'b', 'c'], [a, b, c]);

  [a, b, c] = [a, b, c].sort();
  printThree('After Sorting', ['a', 'b', 'c'], [a, b, c]);

  let x = 77444;
  let y = -12;
  let z = 0;
  printThree('Before Sorting', ['x', 'y', 'z'], [x, y, z]);

  [x, y, z] = [x, y, z].sort();
  printThree('After Sorting', ['x', 'y', 'z'], [x, y, z]);
};
sortThree();
Output:
Before Sorting
    a is: lions, tigers, and
    b is: bears, oh my!
    c is: (from the "Wizard of OZ")
  
After Sorting
    a is: (from the "Wizard of OZ")
    b is: bears, oh my!
    c is: lions, tigers, and
  
Before Sorting
    x is: 77444
    y is: -12
    z is: 0
  
After Sorting
    x is: -12
    y is: 0
    z is: 77444

jq

In this entry, we shall use a JSON object to represent a set of variables and their bindings. jq supports this interpretation: for example, the assignment operator '=' can be used to set the value associated with a key, as in `.x = 0`. jq also allows JSON objects to be specified in a jq program using a JSON-like syntax, e.g. {x: 1}, as illustrated below.

The sorting function defined here is completely generic with respect to the number of variables and the types of their values. For brevity, however, we will only use the required examples.

def example1:
 {x: "lions, tigers, and",
  y: "bears, oh my",
  z: "(from the \"Wizard of OZ\")"
 };

def example2:
 {x: 77444,
  y: -12,
  z: 0
 };

The following sorting function will accept an arbitrary JSON object:

def sortVariables:
  keys_unsorted as $keys
  | ([.[]] | sort) as $values
  | reduce range(0; $keys|length) as $i ({}; .[$keys[$i]] = ($values[$i]) ) ;

Examples:

example1 | sortVariables
Output:
{
  "x": "(from the \"Wizard of OZ\")",
  "y": "bears, oh my",
  "z": "lions, tigers, and"
}
example2 | sortVariables
Output:

{

 "x": -12,
 "y": 0,
 "z": 77444
}

Jsish

#!/usr/bin/env jsish
/* Sort three variables, in Jsish. semi-colon start/end for unit test echo */

var x =  'lions, tigers, and';
var y =  'bears, oh my!';
var z =  '(from the "Wizard of OZ")';

var arr = [x,y,z];
arr = arr.sort();

;'As strings, before:';
;x;
;y;
;z;

x = arr.shift();
y = arr.shift();
z = arr.shift();

;'x,y,z after:';
;x;
;y;
;z;

x =  77444;
y =    -12;
z =      0;

arr = [x,y,z];
arr = arr.sort();

;'As numbers before:';
;x;
;y;
;z;

x = arr.shift();
y = arr.shift();
z = arr.shift();

;'x,y,z after:';
;x;
;y;
;z;

;'Mixed, integer, float, string';
x =  3.14159;
y =  2;
z =  '1 string';
;x;
;y;
;z;
arr = [x,y,z].sort();
x = arr.shift(); y = arr.shift(); z = arr.shift();
;'x,y,z after:';
;x;
;y;
;z;


/*
=!EXPECTSTART!=
'As strings, before:'
x ==> lions, tigers, and
y ==> bears, oh my!
z ==> (from the "Wizard of OZ")
'x,y,z after:'
x ==> (from the "Wizard of OZ")
y ==> bears, oh my!
z ==> lions, tigers, and
'As numbers before:'
x ==> 77444
y ==> -12
z ==> 0
'x,y,z after:'
x ==> -12
y ==> 0
z ==> 77444
'Mixed, integer, float, string'
x ==> 3.14159
y ==> 2
z ==> 1 string
'x,y,z after:'
x ==> 2
y ==> 3.14159
z ==> 1 string
=!EXPECTEND!=
*/
Output:
prompt$ jsish --U sortThree.jsi 
'As strings, before:'
x ==> lions, tigers, and
y ==> bears, oh my!
z ==> (from the "Wizard of OZ")
'x,y,z after:'
x ==> (from the "Wizard of OZ")
y ==> bears, oh my!
z ==> lions, tigers, and
'As numbers before:'
x ==> 77444
y ==> -12
z ==> 0
'x,y,z after:'
x ==> -12
y ==> 0
z ==> 77444
'Mixed, integer, float, string'
x ==> 3.14159
y ==> 2
z ==> 1 string
'x,y,z after:'
x ==> 2
y ==> 3.14159
z ==> 1 string

prompt$ jsish -u sortThree.jsi
[PASS] sortThree.jsi

Julia

# v0.6

a, b, c = "lions, tigers, and", "bears, oh my!", "(from the \"Wizard of OZ\")"
a, b, c = sort([a, b, c])
@show a b c

a, b, c = 77444, -12, 0
a, b, c = sort([a, b, c])
@show a b c
Output:
a = "(from the \"Wizard of OZ\")"
b = "bears, oh my!"
c = "lions, tigers, and"
a = -12
b = 0
c = 77444

Kotlin

Kotlin's standard library contains a sort() function which can sort any generic array whose element type has a defined ordering between its instances. This includes strings, integers and floats examples of which are shown below:

// version 1.1.2

inline fun <reified T : Comparable<T>> sortThree(x: T, y: T, z: T): Triple<T, T, T> {
    val a = arrayOf(x, y, z)
    a.sort()
    return Triple(a[0], a[1], a[2])
}

fun <T> printThree(x: T, y: T, z: T) = println("x = $x\ny = $y\nz = $z\n")

fun main(args: Array<String>) {
    var x = "lions, tigers, and"
    var y = "bears, oh my!"
    var z = """(from the "Wizard of OZ")"""
    val t = sortThree(x, y, z)
    x = t.first
    y = t.second
    z = t.third
    printThree(x, y, z)

    var x2 = 77444
    var y2 = -12
    var z2 = 0 
    val t2 = sortThree(x2, y2, z2)
    x2 = t2.first
    y2 = t2.second
    z2 = t2.third
    printThree(x2, y2, z2)

    var x3 = 174.5
    var y3 = -62.5
    var z3 = 41.7
    val t3 = sortThree(x3, y3, z3)
    x3 = t3.first
    y3 = t3.second
    z3 = t3.third
    printThree(x3, y3, z3)
}
Output:
x = (from the "Wizard of OZ")
y = bears, oh my!
z = lions, tigers, and

x = -12
y = 0
z = 77444

x = -62.5
y = 41.7
z = 174.5

Ksh

#!/bin/ksh

# Sort three variables that may contain any value (numbers and/or literals)

#	# Variables:
#
xl='lions, tigers, and'
yl='bears, oh my!'
zl='(from the "Wizard of OZ")'

typeset -i xn=77444
typeset -F yn=-12.0
typeset -i zn=0

#	# Functions:
#

#	# Function _intoarray(x, y, z, arr) - put 3 variables into arr[]
#
function _intoarray {
	typeset _x ; nameref _x="$1"
	typeset _y ; nameref _y="$2"
	typeset _z ; nameref _z="$3"
	typeset _arr ; nameref _arr="$4"

	_arr=( "${_x}" "${_y}" "${_z}" )
}

#	# Function _arraysort(arr) - return sorted array (any type of elements)
#
function _arraysort {
	typeset _arr ; nameref _arr="$1"
	typeset _i _j ; integer _i _j

	_sorttype _arr
	case $? in
		0)	# Literal sort
			for (( _i=1; _i<${#_arr[*]}; _i++ )); do
				_val="${_arr[_i]}"
				(( _j = _i - 1 ))
				while (( _j>=0 )) && [[ "${_arr[_j]}" > "${_val}" ]]; do
					_arr[_j+1]="${_arr[_j]}"
					(( _j-- ))
				done
				_arr[_j+1]="${_val}"
			done
		;;

		1)	# Numeric sort
			for (( _i=1; _i<${#_arr[*]}; _i++ )); do
				_val=${_arr[_i]}
				(( _j = _i - 1 ))
				while (( _j>=0 && _arr[_j]>_val )); do
					_arr[_j+1]=${_arr[_j]}
					(( _j-- ))
				done
				_arr[_j+1]=${_val}
			done
		;;
	esac
}

#	# Function _sorttype(_arr) - return 0 = Literal sort; 1 = Numeric sort
#
function _sorttype {
	typeset _arr ; nameref _arr="$1"
	typeset _i ; integer _i

	for ((_i=0; _i<${#_arr[*]}; _i++)); do
		[[ ${_arr[_i]} != *(\-)+(\d)*(\.)*(\d) ]] && return 0
	done
	return 1
}

#	# Function _outofarray(x, y, z, arr) - Put array elements into x, y, z
#
function _outofarray {
	typeset _x ; nameref _x="$1"
	typeset _y ; nameref _y="$2"
	typeset _z ; nameref _z="$3"
	typeset _arr ; nameref _arr="$4"

	_x="${_arr[0]}"
	_y="${_arr[1]}"
	_z="${_arr[2]}"
}

 ######
# main #
 ######

unset x y z
printf "Numeric Variables:\n%s\n%s\n%s\n\n" "${xn}" "${yn}" "${zn}"
typeset -a arrayn
_intoarray xn yn zn arrayn
_arraysort arrayn
_outofarray x y z arrayn
printf "Sorted Variables:\n%s\n%s\n%s\n\n" "${x}" "${y}" "${z}"

unset x y z
printf "Literal Variables:\n%s\n%s\n%s\n\n" "${xl}" "${yl}" "${zl}"
typeset -a arrayl
_intoarray xl yl zl arrayl
_arraysort arrayl
_outofarray x y z arrayl
printf "Sorted Variables:\n%s\n%s\n%s\n\n" "${x}" "${y}" "${z}"
Output:

Numeric Variables: 77444 -12.0000000000000 0

Sorted Variables: -12.0000000000000 0 77444

Literal Variables: lions, tigers, and bears, oh my! (from the "Wizard of OZ")

Sorted Variables: bears, oh my! (from the "Wizard of OZ")

lions, tigers, and

Little Man Computer

The LMC in its original form supports only integers in the range 0..999. So the numbers in the task have been changed here from 77444, -12, 0 to 774, 0, 12.

// Little Man Computer
// Sort x, y, z, in ascending order
// Based on a sorting network:
//   if x > z then swap( x, z)
//   if x > y then swap( x, y)
//   if y > z then swap( y, z)
// with the addition that if the 2nd swap is executed
// then the 3rd comparison is not needed.

// Read numbers x, y, z, and display in their original order
        INP
        STA x
        OUT
        INP
        STA y
        OUT
        INP
        STA z
        OUT
// Sort so that x <= y <= z, and display in new order
        LDA z
        SUB x
        BRP label1
        LDA x
        STA t
        LDA z
        STA x
        LDA t
        STA z
label1  LDA y
        SUB x
        BRP label2
        LDA x
        STA t
        LDA y
        STA x
        LDA t
        STA y
        BRA sorted // added to the sorting network
label2  LDA z
        SUB y
        BRP sorted
        LDA y
        STA t
        LDA z
        STA y
        LDA t
        STA z
sorted  LDA x
        OUT
        LDA y
        OUT
        LDA z
        OUT
        HLT
x       DAT
y       DAT
z       DAT
t       DAT
// end
Output:
744
0
12
0
12
744


Lua

Essentially the same as the example algorithm except that the function is variadic. Sorting is done by the in-built table.sort and copying the unknown number of variables in and out of the table is made simple by the (...) in the parameter list and the unpack function respectively.

function variadicSort (...)
  local t = {}
  for _, x in pairs{...} do
    table.insert(t, x)
  end
  table.sort(t)
  return unpack(t)
end

local testCases = {
  { x = 'lions, tigers, and',
    y = 'bears, oh my!',
    z = '(from the "Wizard of OZ")'
  },
  { x = 77444,
    y = -12,
    z = 0
  }
}
for i, case in ipairs(testCases) do
  x, y, z = variadicSort(case.x, case.y, case.z)
  print("\nCase " .. i)
  print("\tx = " .. x)
  print("\ty = " .. y)
  print("\tz = " .. z)
end
Output:
Case 1
        x = (from the "Wizard of OZ")
        y = bears, oh my!
        z = lions, tigers, and

Case 2
        x = -12
        y = 0
        z = 77444

M2000 Interpreter

Variables in M2000 are type of Variant, Interpreter use name type ($) to use proper expression parser something as string. In this example we pass reference from numeric to string identifiers, but data under never moved, so we can read the type, and then we can make second reference to numeric names, and then we use the proper expression parser.

Swap statement swap variants (data), not references, and always swap 16bytes. All arrays are variant type, so we can swap array item with any variable (but names must be the same type - strings or numeric both)

Subs can be found from parent context, but executed like they are in current context. A sub has scope in Module, so can call any sub including itself. For optimization , Interpreter mark in temporary list the sub positions, at the first call. Modules and Functions have a special list, where included at definition time, end excluded when parent exit.

Module Sort3 {
      Let X=77744, Y=-12, Z=0
      Let X$ =  "lions, tigers, and",  Y$ =  "bears, oh my!",  Z$ =  {(from the "Wizard of OZ")}
      \\ & use for by reference pass
      Module SortSome (&X$, &Y$, &Z$){
            If Type$(X$)<>"String" Then {
                  Link X$,Y$, Z$ to X,Y,Z
                  Print3()
                  If Y>Z then Swap Y, Z  ' both numeric in Swap
                  If X>Z then Swap X, Z
                  If X>Y then Swap X, Y 
                  Print3()
            } Else {
                  Print3Str()
                  If Y$>Z$ then Swap Y$, Z$ ' both strings in Swap
                  If X$>Z$ then Swap X$, Z$
                  If X$>Y$ then Swap X$, Y$
                  Print3Str()
            }
      }
      SortSome &X, &Y, &Z
      SortSome &X$, &Y$, &Z$
      Sub Print3()
            \\ double ,, used to insert a New Line
            Print "X=",X,,"Y=",Y,,"Z=",Z
      End Sub
      Sub Print3Str()
            Print "X$=",X$,,"Y$=",Y$,,"Z$=",Z$
      End Sub
}
Sort3

Maple

lst := sort([x,y,z]):
x,y,z := lst[1],lst[2],lst[3]:
Example:

x := 'lions, tigers, and': y := 'bears, oh my!': z := '(from the "Wizard of OZ")':

>>>x;
"(from the "Wizard of OZ")"
>>>y;
"bears, oh my!"
>>>z;
"lions, tigers, and"

x := 77444: y := -12: z := 0:

>>>x;
-12
>>>y;
0
>>>z;
77444

Mathematica/Wolfram Language

All variables in Mathematica are typeless so the follow code works in all cases

{x, y, z} = Sort[{x, y, z}]

example:

x = 77444;
y = -12;
z = 0;
{x, y, z} = Sort[{x, y, z}];
{x, y, z}
Output:
{-12, 0, 77444}

min

Works with: min version 0.19.3

The sort3 operator updates the values of the variables given to it in the calling scope, much like passing by reference. A small drawback is that we must quote the symbols passed in, lest we lose access to them.

(=c =b =a (a -> b -> c ->) => '> sort -> c @ b @ a @) :sort3

"lions, tigers, and" :x
"bears, oh my!" :y
"(from the \"Wizard of OZ\")" :z

'x 'y 'z sort3
x puts!
y puts!
z puts!

77444 :x
-12 :y
0 :z

'x 'y 'z sort3
x puts!
y puts!
z puts!
Output:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and
-12
0
77444

Modula-2

This example does not show the output mentioned in the task description on this page (or a page linked to from here). Please ensure that it meets all task requirements and remove this message.
Note that phrases in task descriptions such as "print and display" and "print and show" for example, indicate that (reasonable length) output be a part of a language's solution.


MODULE SortThreeVariables;
FROM FormatString IMPORT FormatString;
FROM Terminal IMPORT WriteString,WriteLn,ReadChar;

PROCEDURE SwapInt(VAR a,b : INTEGER);
VAR t : INTEGER;
BEGIN
    t := a;
    a := b;
    b := t;
END SwapInt;

PROCEDURE Sort3Int(VAR x,y,z : INTEGER);
BEGIN
    IF x<y THEN
        IF z<x THEN
            SwapInt(x,z);
        END;
    ELSIF y<z THEN
        SwapInt(x,y);
    ELSE
        SwapInt(x,z);
    END;
    IF z<y THEN
        SwapInt(y,z);
    END;
END Sort3Int;

VAR
    buf : ARRAY[0..63] OF CHAR;
    a,b,c : INTEGER;
BEGIN
    a := 77444;
    b := -12;
    c := 0;
    FormatString("Before a=[%i]; b=[%i]; c=[%i]\n", buf, a, b, c);
    WriteString(buf);

    Sort3Int(a,b,c);
    FormatString("Before a=[%i]; b=[%i]; c=[%i]\n", buf, a, b, c);
    WriteString(buf);

    ReadChar;
END SortThreeVariables.

Nanoquery

import sort

// sorting string literals
x = "lion, tigers, and"
y = "bears, oh my!"
z = "(from the \"Wizard of OZ\")"

varlist = sort({x,y,z})

x = varlist[0]
y = varlist[1]
z = varlist[2]
println x; println y; println z

// sorting integers
x = 77444
y = -12
z = 0

varlist = sort({x, y, z})

x = varlist[0]
y = varlist[1]
z = varlist[2]
println x; println y; println z
Output:
(from the "Wizard of OZ")
bears, oh my!
lion, tigers, and
-12
0
77444

Nim

proc sortThree[T](a, b, c: var T) =
  # Bubble sort, why not?
  while not (a <= b and b <= c):
    if a > b: swap a, b
    if b > c: swap b, c

proc testWith[T](a, b, c: T) =
  var (x, y, z) = (a, b, c)
  echo "Before: ", x, ", ", y, ", ", z
  sortThree(x, y, z)
  echo "After: ", x, ", ", y, ", ", z

testWith(6, 4, 2)
testWith(0.9, -37.1, 4.0)
testWith("lions", "tigers", "bears")
Output:
Before: 6, 4, 2
After: 2, 4, 6
Before: 0.9, -37.1, 4.0
After: -37.1, 0.9, 4.0
Before: lions, tigers, bears
After: bears, lions, tigers

OCaml

let sortrefs list =
  let sorted = List.map ( ! ) list
               |> List.sort (fun a b ->
                   if a < b then -1 else
                   if a > b then  1 else
                     0) in
  List.iter2 (fun v x -> v := x) list sorted

open Printf

let test () =
  let x = ref "lions, tigers, and" in
  let y = ref "bears, oh my!" in
  let z = ref "(from the \"Wizard of OZ\")" in
  sortrefs [x; y; z];
  print_endline "case 1:";
  printf "\tx: %s\n" !x;
  printf "\ty: %s\n" !y;
  printf "\tz: %s\n" !z;

  let x = ref 77444 in
  let y = ref (-12) in
  let z = ref 0 in
  sortrefs [x; y; z];
  print_endline "case 1:";
  printf "\tx: %d\n" !x;
  printf "\ty: %d\n" !y;
  printf "\tz: %d\n" !z
Output:
# test ();;
case 1:
  x: (from the "Wizard of OZ")
  y: bears, oh my!
  z: lions, tigers, and
case 1:
  x: -12
  y: 0
  z: 77444
- : unit = ()

Pascal

Works with: Extended Pascal

Pascal is a statically typed programming language. The data types of all variables and routine parameters need to be known in advance. The following program demonstrates sorting three strings, but can be easily adapted to work for integer and real variables as well.

program sortThreeVariables(output);

type
	{ this Extended Pascal data type may hold up to 25 `char` values }
	line = string(25);

{ this procedure sorts two lines }
procedure sortLines(var X, Y: line);
	{ nested procedure allocates space for Z only if needed }
	procedure swap;
	var
		Z: line;
	begin
		Z := X;
		X := Y;
		Y := Z
	end;
begin
	{ for lexical sorting write `if GT(X, Y) then` }
	if X > Y then
	begin
		swap
	end
end;

{ sorts three line variables’s values }
procedure sortThreeLines(var X, Y, Z: line);
begin
	{ `var` parameters can be modified at the calling site }
	sortLines(X, Y);
	sortLines(X, Z);
	sortLines(Y, Z)
end;

{ writes given lines on output preceded by `X = `, `Y = ` and `Z = ` }
procedure printThreeLines(protected X, Y, Z: line);
begin
	{ `protected` parameters cannot be overwritten }
	writeLn('X = ', X);
	writeLn('Y = ', Y);
	writeLn('Z = ', Z)
end;

{ === MAIN ============================================================= }
var
	A, B: line;
	{ for demonstration purposes: alternative method to initialize }
	C: line value '(from the "Wizard of OZ")';
begin
	A := 'lions, tigers, and';
	B := 'bears, oh my!';
	
	sortThreeLines(A, B, C);
	printThreeLines(A, B, C)
end.

Perl

Works with: Perl version 5.10+
#!/usr/bin/env perl
use 5.010_000;

# Sort strings

my $x = 'lions, tigers, and';
my $y = 'bears, oh my!';
my $z = '(from the "Wizard of OZ")';

# When assigning a list to list, the values are mapped
( $x, $y, $z ) = sort ( $x, $y, $z );

say 'Case 1:';
say "  x = $x";
say "  y = $y";
say "  z = $z";

# Sort numbers

$x = 77444;
$y = -12;
$z = 0;

# The sort function can take a customizing block parameter.
# The spaceship operator creates a by-value numeric sort
( $x, $y, $z ) = sort { $a <=> $b } ( $x, $y, $z );

say 'Case 2:';
say "  x = $x";
say "  y = $y";
say "  z = $z";
Output:
Case 1:
  x = (from the "Wizard of OZ")
  y = bears, oh my!
  z = lions, tigers, and

Case 2:
  x = -12
  y = 0
  z = 77444

Phix

Phix is naturally polymorphic

with javascript_semantics
object {x,y,z} = {"lions, tigers, and","bears, oh my","(from the \"Wizard of OZ\")"}
                         ?{x,y,z}
{x,y,z} = sort({x,y,z})  ?{x,y,z}
 
{x,y,z} = {77444,-12,0}  ?{x,y,z}
{x,y,z} = sort({x,y,z})  ?{x,y,z}
Output:
{"lions, tigers, and","bears, oh my","(from the \"Wizard of OZ\")"}
{"(from the \"Wizard of OZ\")","bears, oh my","lions, tigers, and"}
{77444,-12,0}
{-12,0,77444}

PHP

<?php
//Sort strings
$x = 'lions, tigers, and';
$y = 'bears, oh my!';
$z = '(from the "Wizard of OZ")';
$items = [$x, $y, $z];
sort($items);

list($x, $y, $z) = $items;

echo <<<EOT
Case 1:
  x = $x
  y = $y
  z = $z

EOT;

//Sort numbers
$x = 77444;
$y = -12;
$z = 0;
$items = [$x, $y, $z];
sort($items);

list($x, $y, $z) = $items;

echo <<<EOT
Case 2:
  x = $x
  y = $y
  z = $z

EOT;
Output:
Case 1:
  x = (from the "Wizard of OZ")
  y = bears, oh my!
  z = lions, tigers, and
Case 2:
  x = -12
  y = 0
  z = 77444

PicoLisp

(let (X 77444  Y -12  Z 0)
   (println X Y Z)
   (mapc set '(X Y Z) (sort (list X Y Z)))
   (println X Y Z) )
Output:
77444 -12 0
-12 0 77444

Plain English

This will sort integers only.

To run:
Start up.
Sort three numbers.
Wait for the escape key.
Shut down.

To sort three numbers:
Put 77444 into an x number.
Put -12 into a y number.
Put 0 into a z number.
Write "===Before sorting===" on the console.
Write "x: " then the x on the console.
Write "y: " then the y on the console.
Write "z: " then the z on the console.
Sort the x and the y and the z.
Write "===After sorting===" on the console.
Write "x: " then the x on the console.
Write "y: " then the y on the console.
Write "z: " then the z on the console.

To sort a first number and a second number and a third number:
If the first number is greater than the second number, swap the first number with the second number.
If the second number is greater than the third number, swap the second number with the third number.
If the first number is greater than the second number, swap the first number with the second number.
Output:
===Before sorting===
x: 77444
y: -12
z: 0
===After sorting===
x: -12
y: 0
z: 77444

PureBasic

;sort three variables: x, y, z

;Macro handles any of the native types, including integers, floating point, and strings
;because the variable types are not declared but substituted during each instance of the macro.
;The sorting is in ascending order, i.e. x < y < z.
Macro sort3vars(x, y, z)
  If x > y: Swap x, y: EndIf
  If x > z: Swap x, z: EndIf
  If y > z: Swap y, z: EndIf
EndMacro

;Macro to perform the sorting test for each variable type, again by substitution.
Macro test_sort(x, y, z)
  PrintN("Variables before sorting: " + #CRLF$ + x + #CRLF$ + y + #CRLF$ + z + #CRLF$)
  sort3vars(x, y, z)
  
  PrintN("Variables after sorting: " + #CRLF$ + x + #CRLF$ + y + #CRLF$ + z + #CRLF$)
EndMacro


;Define three sets of variables each with a different type for testing
Define.s x, y, z ;string
x = "lions, tigers, and"
y = "bears, oh my!"
z = ~"(from the \"Wizard of OZ\")" ;uses an escaped string as one way to include quotation marks

Define x1 = 77444, y1 = -12, z1 = 0 ;integer

Define.f x2= 5.2, y2 = -1133.9, z2 = 0 ;floating point
If OpenConsole()
  PrintN("Sort three variables" + #CRLF$)
  test_sort(x, y, z) ;strings
  
  test_sort(x1, y1, z1) ;integers
  
  test_sort(x2, y2, z2) ;floating point
  
  Print(#CRLF$ + "Press ENTER to exit"): Input()
  CloseConsole()
EndIf

Sample output:

Sort three variables

Variables before sorting:
lions, tigers, and
bears, oh my!
(from the "Wizard of OZ")

Variables after sorting:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and

Variables before sorting:
77444
-12
0

Variables after sorting:
-12
0
77444

Variables before sorting:
5.1999998093
-1133.9000244141
0

Variables after sorting:
-1133.9000244141
0
5.1999998093

Python

Python2

This solution accepts 3 values either strings or numbers from user and then sort it in ascending order. This is implemented in Python 2.

#python2 Code for Sorting 3 values
a= raw_input("Enter values one by one ..\n1.").strip()
b=raw_input("2.").strip()
c=raw_input("3.").strip()
if a>b :
   a,b = b,a 
if a>c:
   a,c = c,a 
if b>c:
   b,c = c,b 
print(str(a)+" "+str(b)+" "+str(c))

Python3

The following uses Python3.6 f-strings and uses the built in sorted function and assignment to a target list.

while True:
    x, y, z = eval(input('Three Python values: '))
    print(f'As read: x = {x!r}; y = {y!r}; z = {z!r}')
    x, y, z = sorted((x, y, z))
    print(f' Sorted: x = {x!r}; y = {y!r}; z = {z!r}')
Output:
Three Python values: 3, 2, 1
As read: x = 3; y = 2; z = 1
 Sorted: x = 1; y = 2; z = 3

Three Python values: 'lions, tigers, and', 'bears, oh my!', '(from the "Wizard of OZ")'
As read: x = 'lions, tigers, and'; y = 'bears, oh my!'; z = '(from the "Wizard of OZ")'
 Sorted: x = '(from the "Wizard of OZ")'; y = 'bears, oh my!'; z = 'lions, tigers, and'

Three Python values: 77444, -12, 0
As read: x = 77444; y = -12; z = 0
 Sorted: x = -12; y = 0; z = 77444

Three Python values:

Quackery

Quackery does not have variables, instead it has ancillary stacks, which, amongst their uses, can act as variables. Neither does it have operator overloading, so instead we will use sortwith > to sort three integers into ascending numerical order, and sortwith $> to sort three strings into ascending QACSFOT order.

(QACSFOT is the Quackery Arbitrary Character Sequence For Ordered Text, which is 0123456789AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz()[]{}<>~=+-*/^\|_.,:;?!'"`%@&#$. Note that, unlike the even more arbitrary ASCII/Unicode character sequence, all the punctuation marks come after all the alphabetic characters, so the result of sorting the strings will vary from the result given in the task description.)

  [ stack ] is x
  [ stack ] is y
  [ stack ] is z
  
  $ 'lions, tigers, and'        x put
  $ 'bears, oh my!'             y put
  $ '(from the "Wizard of OZ")' z put
  
  x take y take z take
  3 pack sortwith $> unpack
  z put y put x put
  
  say " x = " x take echo$ cr
  say " y = " y take echo$ cr
  say " z = " z take echo$ cr
  
  cr 
  
   77444 x put
  -12    y put
   0     z put
  
  x take y take z take
  3 pack sortwith > unpack
  z put y put x put
  
  say " x = " x take echo cr
  say " y = " y take echo cr
  say " z = " z take echo cr
Output:
 x = bears, oh my!
 y = lions, tigers, and
 z = (from the "Wizard of OZ")

 x = -12
 y = 0
 z = 77444


R

#lang R

assignVec <- Vectorize("assign", c("x", "value"))
`%<<-%` <- function(x, value) invisible(assignVec(x, value, envir = .GlobalEnv)) # define multiple global assignments operator
Output:
x <- 'lions, tigers, and'
y <- 'bears, oh my!'
z <- '(from the "Wizard of OZ")'

c("x", "y", "z") %<<-% sort(c(x, y, z))

x
## [1] "(from the \"Wizard of OZ\")"
y
## [1] "bears, oh my!"
z
## [1] "lions, tigers, and"


x <- 77444
y <-   -12
z <-     0

c("x", "y", "z") %<<-% sort(c(x, y, z))

x
## [1] -12
y
## [1] 0
z
## [1] 77444

Racket

Ugh... mutation. Anyway...

#lang racket

(define-syntax-rule (sort-3! x y z <?)
  (begin
    (define-syntax-rule (swap! x y) (let ((tmp x)) (set! x y) (set! y tmp)))
    (define-syntax-rule (sort-2! x y) (when (<? y x) (swap! x y)))
    (sort-2! x y)
    (sort-2! x z)
    (sort-2! y z)))

(module+ test
  (require rackunit
           data/order)

  (define (test-permutations l <?)
    (test-case
     (format "test-permutations ~a" (object-name <?))
     (for ((p (in-permutations l)))
       (match-define (list a b c) p)
       (sort-3! a b c <?)
       (check-equal? (list a b c) l))))

  (test-permutations '(1 2 3) <)

  ;; string sorting
  (let ((x  "lions, tigers, and")
        (y  "bears, oh my!")
        (z  "(from the \"Wizard of OZ\")"))
    (sort-3! x y z string<?)
    (for-each displayln (list x y z)))

  (newline)

  ;; general data sorting
  (define datum<? (order-<? datum-order))  
  (let ((x  "lions, tigers, and")
        (y  "bears, oh my!")
        (z  '(from the "Wizard of OZ")))
    (sort-3! x y z datum<?)
    (for-each displayln (list x y z))))
Output:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and

bears, oh my!
lions, tigers, and
(from the Wizard of OZ)

Raku

(formerly Perl 6)

Raku has a built in sort routine which uses a variation of quicksort. The built in sort routine will automatically select a numeric sort if given a list of Real numeric items and a lexical Unicode sort if given a list that contains strings. The default numeric sort won't sort complex numbers unless you give it a custom comparator. It is trivial to modify the sort comparator function to get whatever ordering you want though.

The list (77444, -12, 0) is a poor choice to demonstrate numeric sort since it will sort the same numerically or lexically. Instead we'll use (7.7444e4, -12, 18/2). ( A Num, an Int, and a Rat. )

# Sorting strings. Added a vertical bar between strings to make them discernable
my ($a, $b, $c) = 'lions, tigers, and', 'bears,  oh my!', '(from "The Wizard of Oz")';
say "sorting: {($a, $b, $c).join('|')}";
say ($a, $b, $c).sort.join('|'), ' - standard lexical string sort';

# Sorting numeric things
my ($x, $y, $z) = 7.7444e4, -12, 18/2;
say "\nsorting: $x $y $z";
say ($x, $y, $z).sort, ' - standard numeric sort, low to high';

# Or, with a modified comparitor:
for  -*,       ' - numeric sort high to low',
     ~*,       ' - lexical "string" sort',
     *.chars,  ' - sort by string length short to long',
     -*.chars, ' - or long to short'
  -> $comparitor, $type {
    my ($x, $y, $z) = 7.7444e4, -12, 18/2;
    say ($x, $y, $z).sort( &$comparitor ), $type;
}
say '';

# sort ALL THE THINGS
# sorts by lexical order with numeric values by magnitude.
.say for ($a, $b, $c, $x, $y, $z).sort;
Output:
sorting: lions, tigers, and|bears,  oh my!|(from "The Wizard of Oz")
(from "The Wizard of Oz")|bears,  oh my!|lions, tigers, and - standard lexical string sort

sorting: 77444 -12 9
(-12 9 77444) - standard numeric sort, low to high
(77444 9 -12) - numeric sort high to low
(-12 77444 9) - lexical "string" sort
(9 -12 77444) - sort by string length short to long
(77444 -12 9) - or long to short

(from "The Wizard of Oz")
-12
9
77444
bears,  oh my!
lions, tigers, and

Red

Red can natively sort values of various types. For instance here (not exhaustive): strings, integers, floats, characters, IP addresses, email addresses, words (~ variable names).

foreach [x y z] [
	"lions, tigers, and"
	"bears, oh my!"
	{(from the "Wizard of OZ")}
	77444 -12 0
	3.1416 3.1415926 3.141592654
	#"z" #"0" #"A"
	216.239.36.21 172.67.134.114 127.0.0.1
	john@doe.org max@min.com cool@bi.net
	potato carrot cabbage
][
	set [x y z] sort reduce [x y z]
	print ["x:" mold x "y:" mold y "z:" mold z]
]
Output:
x: {(from the "Wizard of OZ")} y: "bears, oh my!" z: "lions, tigers, and"
x: -12 y: 0 z: 77444
x: 3.1415926 y: 3.141592654 z: 3.1416
x: #"0" y: #"A" z: #"z"
x: 127.0.0.1 y: 172.67.134.114 z: 216.239.36.21
x: cool@bi.net y: john@doe.org z: max@min.com
x: cabbage y: carrot z: potato

REXX

Since Classic REXX has no native sorting built-in, here is an alternative algorithm.

generic

This version will sort numbers and/or literals.

The literals can be of any length   (only limited by virtual memory or language limitations).

/*REXX program sorts three (any value)  variables  (X, Y, and  Z)  into ascending order.*/
parse arg x y z .                                /*obtain the three variables from C.L. */
if x=='' | x==","  then x= 'lions, tigers, and'        /*Not specified?  Use the default*/
if y=='' | y==","  then y= 'bears,  oh my!'            /* "      "        "   "     "   */
if z=='' | z==","  then z= '(from "The Wizard of Oz")' /* "      "        "   "     "   */
say '───── original value of X: '   x
say '───── original value of Y: '   y
say '───── original value of Z: '   z
if x>y  then do;   _= x;   x= y;   y= _;   end   /*swap the values of   X   and   Y.    */      /* ◄─── sorting.*/
if y>z  then do;   _= y;   y= z;   z= _;   end   /*  "   "     "    "   Y    "    Z.    */      /* ◄─── sorting.*/
if x>y  then do;   _= x;   x= y;   y= _;   end   /*  "   "     "    "   X    "    Y.    */      /* ◄─── sorting */
say                                              /*stick a fork in it,  we're all done. */
say '═════  sorted  value of X: '   x
say '═════  sorted  value of Y: '   y
say '═════  sorted  value of Z: '   z
output when using the default inputs:
───── original value of X:  lions, tigers, and
───── original value of Y:  bears,  oh my!
───── original value of Z:  (from "The Wizard of Oz")

═════  sorted  value of X:  (from "The Wizard of Oz")
═════  sorted  value of Y:  bears,  oh my!
═════  sorted  value of Z:  lions, tigers, and

numeric only

This version will sort numbers   (the numbers can be in any form, floating point and/or integer).

The maximum integer than be kept   as an integer   is   (in this program)   is 1,000 decimal digits.

/*REXX program sorts  three (numeric)  variables  (X, Y, and  Z)  into ascending order. */
numeric digits 1000                              /*handle some pretty gihugic integers. */      /*can be bigger.*/
parse arg x y z .                                /*obtain the three variables from C.L. */
if x=='' | x==","  then x= 77444                 /*Not specified?  Then use the default.*/
if y=='' | y==","  then y=   -12                 /* "      "         "   "   "     "    */
if z=='' | z==","  then z=     0                 /* "      "         "   "   "     "    */
w= max( length(x), length(y), length(z) )   + 5  /*find max width of the values, plus 5.*/
say '───── original values of X, Y, and Z: '       right(x, w)   right(y, w)   right(z, w)
low = x                                          /*assign a temporary variable.         */
mid = y                                          /*   "   "     "        "              */
high= z                                          /*   "   "     "        "              */
              x= min(low,  mid,  high)           /*determine the lowest value of X,Y,Z. */      /* ◄─── sorting.*/
              z= max(low,  mid,  high)           /*    "      "  highest  "    " " " "  */      /* ◄─── sorting.*/
              y=     low + mid + high - x - z    /*    "      "  middle   "    " " " "  */      /* ◄─── sorting.*/
                                                 /*stick a fork in it,  we're all done. */
say '═════  sorted  values of X, Y, and Z: '    right(x, w)    right(y, w)    right(z, w)
output   when using the default inputs:
───── original values of X, Y, and Z:       77444        -12          0
═════  sorted  values of X, Y, and Z:         -12          0      77444

Ring

# Project : Sort three variables

x = 'lions, tigers, and'
y = 'bears, oh my!'
z = '(from the "Wizard of OZ")'
sortthree(x,y,z)
x = 77444
y = -12
z = 0
sortthree(x,y,z)

func sortthree(x,y,z)
        str = []
        add(str,x)
        add(str,y)
        add(str,z)
        str = sort(str)
        see "x = " + str[1] + nl
        see "y = " + str[2] + nl
        see "z = " + str[3] + nl
        see nl

Output:

x = (from the "Wizard of OZ")
y = bears, oh my!
z = lions, tigers, and

x = -12
y = 0
z = 77444
==Ring==
x = 77444
y = -12
z = 0
sList = sortList(x, y, z)
see sList + nl

x = 'lions, tigers, and'
y = 'bears, oh my!'
z = '(from the "Wizard of OZ")'
sList = sortList(x, y, z)
see sList + nl

func sortList (x, y, z)
     aList = [x, y, z]
     sList = sort(aList)
     return sList

Output:

-12
0
77444

(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and

RPL

Works with: HP version 48
≪ → x y z
  ≪ x y z 3 →LIST SORT LIST→ DROP
≫ ≫ 'SORT3' STO
"lions, tigers, and" "bears, oh my!" "(from the 'Wizard of OZ')" SORT3
77444 -12 9 SORT3
Output:
6: "bears, oh my!"
5: "lions, tigers, and"
4: "(from the 'Wizard of OZ')"
3: -12
2: 9
1: 77444

Ruby

x =  'lions, tigers, and'
y =  'bears, oh my!'
z =  '(from the "Wizard of OZ")'
x, y, z = [x, y, z].sort
puts x, y, z

x, y, z = 7.7444e4, -12, 18/2r # Float, Integer, Rational; taken from Raku
x, y, z = [x, y, z].sort
puts x, y, z
Output:
(from the "Wizard of OZ")
bears, oh my!
lions, tigers, and
-12
9/1
77444.0

Rust

fn main() {
    let mut array = [5, 1, 3];
    array.sort();
    println!("Sorted: {:?}", array);
    array.sort_by(|a, b| b.cmp(a));
    println!("Reverse sorted: {:?}", array);
}

Scala

As a Functional Programming language embraces the use of immutable variables. Mutability (variables and states) is seen as evil. Scala works rather with transformed collection obtained by functions then mutable variable and variable state. So this task has no sense in modern programming.

Seed7

$ include "seed7_05.s7i";

const proc: genSort3 (in type: elemType) is func
  begin
    global

    const proc: doSort3 (in var elemType: x, in var elemType: y, in var elemType: z) is func
      local
        var array elemType: sorted is 0 times elemType.value;
      begin
        writeln("BEFORE: x=[" <& x <& "]; y=[" <& y <& "]; z=[" <& z <& "]");
        sorted := sort([](x, y, z));
        x := sorted[1];
        y := sorted[2];
        z := sorted[3];
        writeln("AFTER: x=[" <& x <& "]; y=[" <& y <& "]; z=[" <& z <& "]");
      end func;

    end global;
  end func;

genSort3(integer);
genSort3(string);

const proc: main is func
  begin
    doSort3(77444, -12, 0);
    doSort3("lions, tigers, and", "bears, oh my!", "(from the \"Wizard of OZ\")");
  end func;
Output:
BEFORE: x=[77444]; y=[-12]; z=[0]
AFTER: x=[-12]; y=[0]; z=[77444]
BEFORE: x=[lions, tigers, and]; y=[bears, oh my!]; z=[(from the "Wizard of OZ")]
AFTER: x=[(from the "Wizard of OZ")]; y=[bears, oh my!]; z=[lions, tigers, and]

SenseTalk

Set x to "lions, tigers and"
Set y to "bears, oh my!" 
Set z to "(from the Wizard of Oz)"
log x
log y
log z

set RosettaListAlpha to (x,y,z)
log RosettaListAlpha
sort RosettaListAlpha alphabetically
log RosettaListAlpha

LogSuccess "Alphabetical Sort Successful"

set (x,y,z) to RosettaListAlpha
log x 
log y
log z

LogSuccess "Sorted Items back into Original Variables"

Set a to "77444"
set b to "-12"
set c to "0"
set d to "62224"

set RosettaListNum to (a,b,c,d)
log RosettaListNum
sort RosettaListNum numerically
log RosettaListNum

LogSuccess "Numerical Sort Successful"

set (a,b,c,d) to RosettaListNum
log a
log b
log c
log d

LogSuccess "Sorted Numbers back into Original Variables"

Sidef

Generalized solution, for an arbitrary number of variable references:

func sort_refs(*arr) {
    arr.map{ *_ }.sort ~Z arr -> each { *_[1] = _[0] }
}

var x = 77444
var y =   -12
var z =     0

sort_refs(\x, \y, \z)

say x
say y
say z
Output:
-12
0
77444

Alternatively, without using a sorting function:

var x = 77444
var y =   -12
var z =     0

(x, y) = (y, x) if (x > y)
(x, z) = (z, x) if (x > z)
(y, z) = (z, y) if (y > z)

say x
say y
say z
Output:
-12
0
77444

Swift

func varSort<T: Comparable>(_ x: inout T, _ y: inout T, _ z: inout T) {
  let res = [x, y, z].sorted()

  x = res[0]
  y = res[1]
  z = res[2]
}

var x = "lions, tigers, and"
var y = "bears, oh my!"
var z = "(from the \"Wizard of OZ\")"

print("Before:")
print("x = \(x)")
print("y = \(y)")
print("z = \(z)")
print()

varSort(&x, &y, &z)

print("After:")
print("x = \(x)")
print("y = \(y)")
print("z = \(z)")
Output:
Before:
x = lions, tigers, and
y = bears, oh my!
z = (from the "Wizard of OZ")

After:
x = (from the "Wizard of OZ")
y = bears, oh my!
z = lions, tigers, and

Tcl

set x {lions, tigers, and}
set y {bears, oh my!}
set z {(from the "Wizard of OZ")}

lassign [lsort [list $x $y $z]] x y z

puts "x: $x"
puts "y: $y"
puts "z: $z"


set x 77444
set y -12
set z 0

lassign [lsort [list $x $y $z]] x y z

puts "x: $x"
puts "y: $y"
puts "z: $z"
Output:
x: (from the "Wizard of OZ")
y: bears, oh my!
z: lions, tigers, and
x: -12
y: 0
z: 77444

TXR

The following is a comprehensive solution to the general problem of sorting any number of mutable places. We develop a macro operator called sort-places which is called with zero or more argument expressions that denote assignable places. The places are sorted in order according to the greater function.

The zero and one argument cases are handled as no-ops; the arguments are not evaluated at all, even for their side effects if they have any. The two argument case is handled by generating a conditional which controls a single swap. The three-argument case performs up to three swaps.

For four or more arguments, a hidden vector object is generated. The values of the places are stuffed into the vector, which is then sorted, after which the values are retrieved and stored in the places.

All cases work in such a way that the place expressions are evaluated at most once, which is achieved by leveraging the simple-to-use placelet macro.

(defmacro sort-places (. places)
  (caseql (len places)
    ((0 1) nil)
    (2 (with-gensyms (p0 p1)
         ^(placelet ((p0 (read-once ,[places 0]))
                     (p1 (read-once ,[places 1])))
            (if (greater p0 p1)
              (swap p0 p1)))))
    (3 (with-gensyms (p0 p1 p2)
         ^(placelet ((p0 (read-once ,[places 0]))
                     (p1 (read-once ,[places 1]))
                     (p2 (read-once ,[places 2])))
            (if (greater p0 p1)
              (swap p0 p1))
            (if (greater p1 p2)
              (swap p1 p2))
            (if (greater p0 p1)
              (swap p0 p1)))))
    (t (let ((gens [mapcar (ret (gensym)) places]))
         (with-gensyms (vec)
           ^(placelet ,(zip gens places)
              (let ((,vec (vec ,*gens)))
                (nsort ,vec)
                (set ,*(append-each ((g gens)
                                     (i 0))
                         ^(,g [,vec ,i]))))))))))

(prinl (sort-places))

(let ((x 1))
  (sort-places x)
  (prinl x))

(let ((x 2)
      (y 1))
  (sort-places x y)
  (prinl (list x y)))

(let ((a 3)
      (b 2)
      (c 1))
  (sort-places a b c)
  (prinl (list a b c)))

(let ((a 4)
      (b 3)
      (c 2)
      (d 1))
  (sort-places a b c d)
  (prinl (list a b c d)))
Output:
nil
1
(1 2)
(1 2 3)
(1 2 3 4)

Visual Basic .NET

Translation of: C#
Module Module1

    Sub Swap(Of T)(ByRef a As T, ByRef b As T)
        Dim c = a
        a = b
        b = c
    End Sub

    Sub Sort(Of T As IComparable(Of T))(ByRef a As T, ByRef b As T, ByRef c As T)
        If a.CompareTo(b) > 0 Then
            Swap(a, b)
        End If
        If a.CompareTo(c) > 0 Then
            Swap(a, c)
        End If
        If b.CompareTo(c) > 0 Then
            Swap(b, c)
        End If
    End Sub

    Sub Main()
        Dim x = 77444
        Dim y = -12
        Dim z = 0
        Sort(x, y, z)
        Console.WriteLine((x, y, z))

        Dim a = "lions, tigers, and"
        Dim b = "bears, oh my!"
        Dim c = "(from the 'Wizard of OZ')"
        Sort(a, b, c)
        Console.WriteLine((a, b, c))
    End Sub

End Module
Output:
(-12, 0, 77444)
((from the 'Wizard of OZ'), bears, oh my!, lions, tigers, and)

Wren

Library: Wren-sort
Library: Wren-fmt
import "./sort" for Sort
import "./fmt" for Fmt

var sort3 = Fn.new { |x, y, z|
    var a = [x, y, z]
    Sort.insertion(a)
    x = a[0]
    y = a[1]
    z = a[2]
    Fmt.print("  x = $s\n  y = $s\n  z = $s", x, y, z)
}

System.print("After sorting strings:")
var x = "lions, tigers, and"
var y = "bears, oh my!"
var z = "(from the \"Wizard of OZ\")"
sort3.call(x, y, z)

System.print("\nAfter sorting integers:")
x = 77444
y = -12
z = 0
sort3.call(x, y, z)

System.print("\nAfter sorting floats:")
x = 11.3
y = -9.7
z = 11.17
sort3.call(x, y, z)
Output:
After sorting strings:
  x = (from the "Wizard of OZ")
  y = bears, oh my!
  z = lions, tigers, and

After sorting integers:
  x = -12
  y = 0
  z = 77444

After sorting floats:
  x = -9.7
  y = 11.17
  z = 11.3

zkl

This solution uses list assignment and list sorting. Lists are not homogeneous, but sorting usually expects that. If that is a problem, you can give the sort a compare function. Numbers (real and integer) are homogeneous enough to sort.

x,y,z := "lions, tigers, and", "bears, oh my!", 0'|(from the "Wizard of OZ")|;
x,y,z = List(x,y,z).sort();
println(x," | ",y," | ",z);

x,y,z := 77444, -12, 0;
x,y,z = List(x,y,z).sort();
println(x," ",y," ",z);
Output:
(from the "Wizard of OZ") | bears, oh my! | lions, tigers, and
-12 0 77444