Order two numerical lists

Order two numerical lists
You are encouraged to solve this task according to the task description, using any language you may know.

Tasks in this category have to do with sorting collections of objects.

Sorting Algorithm
This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or:

O(n logn) sorts

Heap sort | Merge sort | Patience sort | Quick sort

O(n log²n) sorts
Shell Sort

O(n²) sorts
Bubble sort | Cocktail sort | Cocktail sort with shifting bounds | Comb sort | Cycle sort | Gnome sort | Insertion sort | Selection sort | Strand sort

other sorts
Bead sort | Bogo sort | Common sorted list | Composite structures sort | Custom comparator sort | Counting sort | Disjoint sublist sort | External sort | Jort sort | Lexicographical sort | Natural sorting | Order by pair comparisons | Order disjoint list items | Order two numerical lists | Object identifier (OID) sort | Pancake sort | Quickselect | Permutation sort | Radix sort | Ranking methods | Remove duplicate elements | Sleep sort | Stooge sort | [Sort letters of a string] | Three variable sort | Topological sort | Tree sort

Write a function that orders two lists or arrays filled with numbers. The function should accept two lists as arguments and return true if the first list should be ordered before the second, and false otherwise.

The order is determined by lexicographic order: Comparing the first element of each list. If the first elements are equal, then the second elements should be compared, and so on, until one of the list has no more elements. If the first list runs out of elements the result is true. If the second list or both run out of elements the result is false.

Note: further clarification of lexicographical ordering is expounded on the talk page here and here.

11l

Translation of: Python

[1,2,1,3,2] < [1,2,0,4,4,0,0,0]

AArch64 Assembly

Works with: as version Raspberry Pi 3B version Buster 64 bits

/* ARM assembly AARCH64 Raspberry PI 3B */
/*  program orderlist64.s   */

/*******************************************/
/* Constantes file                         */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM64.inc" 

/*********************************/
/* Initialized data              */
/*********************************/
.data
szMessResult1:      .asciz "List1 < List2 \n"           // message result
szMessResult2:      .asciz "List1 => List2 \n"           // message result
szCarriageReturn:  .asciz "\n"
 
qTabList1:         .quad  1,2,3,4,5
.equ NBELEMENTS1,   (. - qTabList1) /8
qTabList2:         .quad  1,2,1,5,2,2
.equ NBELEMENTS2,   (. - qTabList2) /8
qTabList3:         .quad  1,2,3,4,5
.equ NBELEMENTS3,   (. - qTabList3) /8
qTabList4:         .quad  1,2,3,4,5,6
.equ NBELEMENTS4,   (. - qTabList4) /8
/*********************************/
/* UnInitialized data            */
/*********************************/
.bss 
/*********************************/
/*  code section                 */
/*********************************/
.text
.global main 
main:                                       // entry of program 
    ldr x0,qAdriTabList1
    mov x1,NBELEMENTS1
    ldr x2,qAdriTabList2
    mov x3,NBELEMENTS2
    bl listeOrder
    cmp x0,0                                // false ?
    beq 1f                                  // yes
    ldr x0,qAdrszMessResult1                // list 1 < list 2
    bl affichageMess                        // display message
    b 2f
1:
    ldr x0,qAdrszMessResult2
    bl affichageMess                        // display message
 
2:
    ldr x0,qAdriTabList1
    mov x1,NBELEMENTS1
    ldr x2,qAdriTabList3
    mov x3,NBELEMENTS3
    bl listeOrder
    cmp x0,0                               // false ?
    beq 3f                                  // yes
    ldr x0,qAdrszMessResult1                // list 1 < list 2
    bl affichageMess                        // display message
    b 4f
3:
    ldr x0,qAdrszMessResult2
    bl affichageMess                        // display message
4:
    ldr x0,qAdriTabList1
    mov x1,NBELEMENTS1
    ldr x2,qAdriTabList4
    mov x3,NBELEMENTS4
    bl listeOrder
    cmp x0,0                               // false ?
    beq 5f                                  // yes
    ldr x0,qAdrszMessResult1                // list 1 < list 2
    bl affichageMess                        // display message
    b 6f
5:
    ldr x0,qAdrszMessResult2
    bl affichageMess                        // display message
6:
100:                                        // standard end of the program 
    mov x0,0                              // return code
    mov x8,EXIT                           // request to exit program
    svc 0                                  // perform the system call
qAdriTabList1:             .quad qTabList1
qAdriTabList2:             .quad qTabList2
qAdriTabList3:             .quad qTabList3
qAdriTabList4:             .quad qTabList4
qAdrszMessResult1:         .quad szMessResult1
qAdrszMessResult2:         .quad szMessResult2
qAdrszCarriageReturn:      .quad szCarriageReturn
/******************************************************************/
/*     liste order                                                */ 
/******************************************************************/
/* x0 contains the address of list 1 */
/* x1 contains list 1 size           */
/* x2 contains the address of list 2 */
/* x3 contains list 2 size           */
/* x0 returns 1 if list1 < list2     */
/* x0 returns 0 else                 */
listeOrder:
    stp x1,lr,[sp,-16]!          // save  registers
    stp x2,x3,[sp,-16]!          // save  registers
    cbz x1,99f                    // list 1 size = zero ?
    cbz x3,98f                    // list 2 size = zero ?

    mov x4,#0                    // index list 1
    mov x5,#0                    // index list 2
1:
    ldr x6,[x0,x4,lsl #3]        // load list 1 element
    ldr x8,[x2,x5,lsl #3]        // load list 2 element
    cmp x6,x8                    // compar
    bgt 4f
    beq 2f                       // list 1 = list 2
    add x4,x4,1                  // increment index 1
    cmp x4,x1                    // end list ?
    bge 5f
    b 1b                         // else loop
2:
    add x4,x4,1                  // increment index 1
    cmp x4,x1                    // end list ?
    bge 3f                       // yes -> verif size
    add x5,x5,1                  // else increment index 2
    cmp x5,x3                    // end list 2 ?
    bge 4f
    b 1b                         // else loop
3:
    cmp x1,x3                     // compar size
    bge 4f                       // list 2 < list 1
    blt 5f                       // list 1 < list 2
    b 100f
4:
    mov x0,#0                    // list 1 > list 2
    b 100f
5:
    mov x0,#1                    //  list 1 < list 2
    b 100f
98:                              // error
    mov x0,-2
    b 100f
99:                              // error
    mov x0,-1
100:
    ldp x2,x3,[sp],16            // restaur  2 registers
    ldp x1,lr,[sp],16            // restaur  2 registers
    ret                          // return to address lr x30
/********************************************************/
/*        File Include fonctions                        */
/********************************************************/
/* for this file see task include a file in language AArch64 assembly */
.include "../includeARM64.inc"

ACL2

The built-in lexorder does this.

ACL2 !>(lexorder '(1 2 3) '(1 2 3 4))
T
ACL2 !>(lexorder '(1 2 4) '(1 2 3))
NIL

Action!

INT FUNC Compare(INT ARRAY x INT xLen INT ARRAY y INT yLen)
  INT i,len

  len=xLen
  IF len>yLen THEN
    len=yLen
  FI
  FOR i=0 TO len-1
  DO
    IF x(i)>y(i) THEN
      RETURN (1)
    ELSEIF x(i)<y(i) THEN
      RETURN (-1)
    FI
  OD
  IF xLen>yLen THEN
    RETURN (1)
  ELSEIF xLen<yLen THEN
    RETURN (-1)
  FI
RETURN (0)

BYTE FUNC Less(INT ARRAY x INT xLen INT ARRAY y INT yLen)
  IF Compare(x,xLen,y,yLen)<0 THEN
    RETURN (1)
  FI
RETURN (0)

PROC PrintArray(INT ARRAY x INT len)
  INT i

  Put('[)
  FOR i=0 TO len-1
  DO
    PrintI(x(i))
    IF i<len-1 THEN
      Put(' )
    FI
  OD
  Put('])
RETURN

PROC Test(INT ARRAY x INT xLen INT ARRAY y INT yLen)
  PrintArray(x,xLen)
  IF Less(x,xLen,y,yLen) THEN
     Print(" < ")
  ELSE
    Print(" >= ")
  FI
  PrintArray(y,yLen) PutE()
RETURN

PROC Main()
  INT ARRAY a=[1 2 1 5 2]
  INT ARRAY b=[1 2 1 5 2 2]
  INT ARRAY c=[1 2 3 4 5]
  INT ARRAY d=[1 2 3 4 5]
  
  Test(a,5,b,6)
  Test(b,6,a,5)
  Test(b,6,c,5)
  Test(c,5,b,6)
  Test(c,5,d,5)
RETURN

Output:

Screenshot from Atari 8-bit computer

[1 2 1 5 2] < [1 2 1 5 2 2]
[1 2 1 5 2 2] >= [1 2 1 5 2]
[1 2 1 5 2 2] < [1 2 3 4 5]
[1 2 3 4 5] >= [1 2 1 5 2 2]
[1 2 3 4 5] >= [1 2 3 4 5]

Ada

This is already implemented in the built-in comparison operators for arrays of types that have a direct ordering. This also includes arrays of user defined types, using the type definition order from smallest to largest. Demonstrated in the program below:

with Ada.Text_IO;  use Ada.Text_IO;
procedure Order is

   type IntArray is array (Positive range <>) of Integer;
   List1 : IntArray := (1, 2, 3, 4, 5);
   List2 : IntArray := (1, 2, 1, 5, 2, 2);
   List3 : IntArray := (1, 2, 1, 5, 2);
   List4 : IntArray := (1, 2, 1, 5, 2);

   type Animal is (Rat, Cat, Elephant);
   type AnimalArray is array (Positive range <>) of Animal;
   List5 : AnimalArray := (Cat, Elephant, Rat, Cat);
   List6 : AnimalArray := (Cat, Elephant, Rat);
   List7 : AnimalArray := (Cat, Cat, Elephant);

begin
   Put_Line (Boolean'Image (List1 > List2)); --  True
   Put_Line (Boolean'Image (List2 > List3)); --  True
   Put_Line (Boolean'Image (List3 > List4)); --  False, equal
   Put_Line (Boolean'Image (List5 > List6)); --  True
   Put_Line (Boolean'Image (List6 > List7)); --  True
end Order;

Output:

TRUE
TRUE
FALSE
TRUE
TRUE

ALGOL 68

BEGIN # compare lists (rows) of integers #
    # returns TRUE if there is an element in a that is < the corresponding #
    # element in b and all previous elements are equal; FALSE otherwise    #
    OP < = ( []INT a, b )BOOL:
       IF  INT  a pos  := LWB a;
           INT  b pos  := LWB b;
           BOOL equal  := TRUE;
           WHILE a pos <= UPB a AND b pos <= UPB b AND equal DO
               equal := a[ a pos ] = b[ b pos ];
               IF equal THEN
                   a pos +:= 1;
                   b pos +:= 1
               FI
           OD;
           NOT equal
       THEN
           # there is an element in a and b that is not equal #
           a[ a pos ] < b[ b pos ]
       ELSE
           # all elements are equal or one list is shorter #
           # a is < b if a has fewer elements #
           a pos > UPB a AND b pos <= UPB b
       FI # < # ;

    # tests a < b has the expected result #
    PROC test = ( STRING a name, []INT a, STRING b name, []INT b, BOOL expected )VOID:
         BEGIN
            BOOL result = a < b;
            print( ( a name, IF result THEN " <  " ELSE " >= " FI, b name
                   , IF result = expected THEN "" ELSE ", NOT as expected" FI
                   , newline
                   )
                 )
         END # test # ;

    # test cases as in the BBC basic sample #
    []INT list1 = ( 1, 2, 1, 5, 2 );
    []INT list2 = ( 1, 2, 1, 5, 2, 2 );
    []INT list3 = ( 1, 2, 3, 4, 5 );
    []INT list4 = ( 1, 2, 3, 4, 5 );
    test( "list1", list1, "list2", list2, TRUE  );
    test( "list2", list2, "list3", list3, TRUE  );
    test( "list3", list3, "list4", list4, FALSE );

    # additional test cases #
    []INT list5 = ( 9, 0, 2, 1, 0 );
    []INT list6 = ( 4, 0, 7, 7 );
    []INT list7 = ( 4, 0, 7    );
    []INT list8 = ( );
    test( "list5", list5, "list6", list6, FALSE );
    test( "list6", list6, "list7", list7, FALSE );
    test( "list7", list7, "list8", list8, FALSE );
    test( "list8", list8, "list7", list7, TRUE  )

END

Output:

list1 <  list2
list2 <  list3
list3 >= list4
list5 >= list6
list6 >= list7
list7 >= list8
list8 <  list7

ALGOL W

Translation of: ALGOL 68

begin % compare lists (rows) of integers %
    % returns TRUE if there is an element in a that is < the corresponding %
    % element in b and all previous elements are equal, FALSE otherwise    %
    % the bounds of a and b should aLb :: aUb and bLb :: bUb               %
    logical procedure iLT ( integer array a ( * )
                          ; integer value aLb, aUb
                          ; integer array b ( * )
                          ; integer value bLb, bUb
                          ) ;
    begin
        integer aPos, bPos;
        logical equal;
        aPos := aLb;
        bPos := bLb;
        equal := true;
        while aPos <= aUb and bPos <= bUb and equal do begin
            equal := a( aPos ) = b( bPos );
            if equal then begin
                aPos := aPOs + 1;
                bPos := bPos + 1
           end if_equal
        end while_more_elements_and_equal ;
        if not equal
        then % there is an element in a and b that is not equal %
             a( aPos ) < b( bPos )
        else % all elements are equal or one list is shorter %
             % a is < b if a has fewer elements %
             aPos > aUb and bPos <= bUb
    end iLT ;
    % tests a < b has the expected result %
    procedure test ( string(5) value aName
                   ; integer array a ( * )
                   ; integer value aLb, aUb
                   ; string(5) value bName
                   ; integer array b ( * )
                   ; integer value bLb, bUb
                   ; logical value expected
                   ) ;
    begin
        logical isLt;
        isLt := iLT( a, aLb, aUb, b, bLb, bUb );
        write( aName, if isLt then " <  " else " >= ", bName
             , if isLt = expected then "" else ", NOT as expected"
             )
    end test ;

    integer array list1, list3, list4 ( 1 :: 5 );
    integer array list2               ( 1 :: 6 );
    integer array list5               ( 1 :: 5 );
    integer array list6               ( 1 :: 4 );
    integer array list7               ( 1 :: 3 );
    integer array list8               ( 1 :: 1 );
    integer aPos;
    % test cases as in the BBC basic sample %
    aPos := 1; for i := 1, 2, 1, 5, 2    do begin list1( aPos ) := i; aPos := aPos + 1 end;
    aPos := 1; for i := 1, 2, 1, 5, 2, 2 do begin list2( aPos ) := i; aPos := aPos + 1 end;
    aPos := 1; for i := 1, 2, 3, 4, 5    do begin list3( aPos ) := i; aPos := aPos + 1 end;
    aPos := 1; for i := 1, 2, 3, 4, 5    do begin list4( aPos ) := i; aPos := aPos + 1 end;
    test( "list1", list1, 1, 5, "list2", list2, 1, 6, true  );
    test( "list2", list2, 1, 6, "list3", list3, 1, 5, true  );
    test( "list3", list3, 1, 5, "list4", list4, 1, 5, false );
    % additional test cases %
    aPos := 1; for i := 9, 0, 2, 1, 0    do begin list5( aPos ) := i; aPos := aPos + 1 end;
    aPos := 1; for i := 4, 0, 7, 7       do begin list6( aPos ) := i; aPos := aPos + 1 end;
    aPos := 1; for i := 4, 0, 7          do begin list7( aPos ) := i; aPos := aPos + 1 end;
    test( "list5", list5, 1, 5, "list6", list6, 1, 4, false );
    test( "list6", list6, 1, 4, "list7", list7, 1, 3, false );
    test( "list7", list7, 1, 3, "list8", list8, 1, 0, false );
    test( "list8", list8, 1, 0, "list7", list7, 1, 3, true  )
end.

Output:

list1 <  list2
list2 <  list3
list3 >= list4
list5 >= list6
list6 >= list7
list7 >= list8
list8 <  list7

Aime

ordl(list a, b)
{
    integer i, l, o;

    l = min(~a, ~b);
    i = 0;
    while (i < l) {
        if (a[i] != b[i]) {
            o = a[i] < b[i];
            break;
        }

        i += 1;
    }

    i < l ? o : ~a <= ~b;
}

main(void)
{
    o_(ordl(list(1, 2), list(1, 2)), "\n");
    o_(ordl(list(1e2, 2), list(1e2, 2, 3)), "\n");
    o_(ordl(list(1, 2, 3), list(1, 2)), "\n");
    o_(ordl(list(.5, 4), list(.5, 2)), "\n");
    o_(ordl(list(1, 4, 2, 3), list(1, 4, 2.1, 3)), "\n");

    0;
}

AppleScript

Translation of: JavaScript

<= is not defined over lists in AppleScript

-- <= for lists
-- compare :: [a] -> [a] -> Bool
on compare(xs, ys)
    if length of xs = 0 then
        true
    else
        if length of ys = 0 then
            false
        else
            set {hx, txs} to uncons(xs)
            set {hy, tys} to uncons(ys)
            
            if hx = hy then
                compare(txs, tys)
            else
                hx < hy
            end if
        end if
    end if
end compare



-- TEST
on run
    
    {compare([1, 2, 1, 3, 2], [1, 2, 0, 4, 4, 0, 0, 0]), ¬
        compare([1, 2, 0, 4, 4, 0, 0, 0], [1, 2, 1, 3, 2])}
    
end run


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

-- GENERIC FUNCTION

-- uncons :: [a] -> Maybe (a, [a])
on uncons(xs)
    if length of xs > 0 then
        {item 1 of xs, rest of xs}
    else
        missing value
    end if
end uncons

Output:

{false, true}

---

Here's an iterative implementation:

on listAComesBeforeListB(a, b)
    set aLength to (count a)
    set bLength to (count b)
    set i to 0
    repeat
        set i to i + 1
        if (i > bLength) then
            return false
        else if (i > aLength) then
            return true
        else
            set aVal to item i of a
            set bVal to item i of b
            if (aVal = bVal) then
            else
                return (bVal > aVal)
            end if
        end if
    end repeat
end listAComesBeforeListB

-- Test code:
set a to {}
repeat (random number 10) times
    set end of a to random number 10
end repeat
set b to {}
repeat (random number 10) times
    set end of b to random number 10
end repeat

return {a:a, b:b, | a < b |: listAComesBeforeListB(a, b)},

Output:

Examples:

{a:{3, 5, 6, 5, 2, 1, 4}, b:{5, 8, 9, 2, 0, 1, 9, 0, 4, 10}, | a < b |:true}
{a:{10, 9, 5, 8, 8, 4, 3}, b:{5, 10, 8, 9, 10, 8, 7, 8}, | a < b |:false}
{a:{0, 10}, b:{0, 10}, | a < b |:false}
{a:{0, 10}, b:{0, 10, 5}, | a < b |:true}

ARM Assembly

Works with: as version Raspberry Pi

/* ARM assembly Raspberry PI  */
/*  program orderlist.s   */

/* Constantes    */
.equ STDOUT, 1     @ Linux output console
.equ EXIT,   1     @ Linux syscall
.equ WRITE,  4     @ Linux syscall

/*********************************/
/* Initialized data              */
/*********************************/
.data
szMessResult1:      .asciz "List1 < List2 \n"           @ message result
szMessResult2:      .asciz "List1 => List2 \n"           @ message result
szCarriageReturn:  .asciz "\n"

iTabList1:         .int  1,2,3,4,5
.equ NBELEMENTS1,   (. - iTabList1) /4
iTabList2:         .int  1,2,1,5,2,2
.equ NBELEMENTS2,   (. - iTabList2) /4
iTabList3:         .int  1,2,3,4,5
.equ NBELEMENTS3,   (. - iTabList3) /4
iTabList4:         .int  1,2,3,4,5,6
.equ NBELEMENTS4,   (. - iTabList4) /4
/*********************************/
/* UnInitialized data            */
/*********************************/
.bss 
/*********************************/
/*  code section                 */
/*********************************/
.text
.global main 
main:                                       @ entry of program 
    ldr r0,iAdriTabList1
    mov r1,#NBELEMENTS1
    ldr r2,iAdriTabList2
    mov r3,#NBELEMENTS2
    bl listeOrder
    cmp r0,#0                               @ false ?
    beq 1f                                  @ yes
    ldr r0,iAdrszMessResult1                @ list 1 < list 2
    bl affichageMess                        @ display message
    b 2f
1:
    ldr r0,iAdrszMessResult2
    bl affichageMess                        @ display message

2:
    ldr r0,iAdriTabList1
    mov r1,#NBELEMENTS1
    ldr r2,iAdriTabList3
    mov r3,#NBELEMENTS3
    bl listeOrder
    cmp r0,#0                               @ false ?
    beq 3f                                  @ yes
    ldr r0,iAdrszMessResult1                @ list 1 < list 2
    bl affichageMess                        @ display message
    b 4f
3:
    ldr r0,iAdrszMessResult2
    bl affichageMess                        @ display message
4:
    ldr r0,iAdriTabList1
    mov r1,#NBELEMENTS1
    ldr r2,iAdriTabList4
    mov r3,#NBELEMENTS4
    bl listeOrder
    cmp r0,#0                               @ false ?
    beq 5f                                  @ yes
    ldr r0,iAdrszMessResult1                @ list 1 < list 2
    bl affichageMess                        @ display message
    b 6f
5:
    ldr r0,iAdrszMessResult2
    bl affichageMess                        @ display message
6:
100:                                        @ standard end of the program 
    mov r0, #0                              @ return code
    mov r7, #EXIT                           @ request to exit program
    svc #0                                  @ perform the system call
iAdriTabList1:             .int iTabList1
iAdriTabList2:             .int iTabList2
iAdriTabList3:             .int iTabList3
iAdriTabList4:             .int iTabList4
iAdrszMessResult1:        .int szMessResult1
iAdrszMessResult2:        .int szMessResult2
iAdrszCarriageReturn:     .int szCarriageReturn
/******************************************************************/
/*     display text with size calculation                         */ 
/******************************************************************/
/* r0 contains the address of list 1 */
/* r1 contains list 1 size           */
/* r2 contains the address of list 2 */
/* r3 contains list 2 size           */
/* r0 returns 1 if list1 < list2     */
/* r0 returns 0 else                 */
listeOrder:
    push {r1-r7,lr}                   @ save  registres
    cmp r1,#0                         @ list 1 size = zero ?
    moveq r0,#-1                      @ yes -> error
    beq 100f
    cmp r3,#0                         @ list 2 size = zero ?
    moveq r0,#-2                      @ yes -> error
    beq 100f
    mov r4,#0                         @ index list 1
    mov r5,#0                         @ index list 2
1:
    ldr r6,[r0,r4,lsl #2]             @ load list 1 element
    ldr r7,[r2,r5,lsl #2]             @ load list 2 element
    cmp r6,r7                         @ compar
    movgt r0,#0                       @ list 1 > list 2 ?
    bgt 100f
    beq 2f                            @ list 1 = list 2
    add r4,#1                         @ increment index 1
    cmp r4,r1                         @ end list ?
    movge r0,#1                       @ yes -> ok list 1 < list 2
    bge 100f
    b 1b                              @ else loop
2:
    add r4,#1                         @ increment index 1
    cmp r4,r1                         @ end list ?
    bge 3f                            @ yes -> verif size
    add r5,#1                         @ else increment index 2
    cmp r5,r3                         @ end list 2 ?
    movge r0,#0                       @ yes -> list 2 < list 1
    bge 100f
    b 1b                              @ else loop
3:
   cmp r1,r3                          @ compar size
   movge r0,#0                        @ list 2 < list 1
   movlt r0,#1                        @ list 1 < list 2
100:
    pop {r1-r7,lr}                    @ restaur registers
    bx lr                             @ return  
/******************************************************************/
/*     display text with size calculation                         */ 
/******************************************************************/
/* r0 contains the address of the message */
affichageMess:
    push {r0,r1,r2,r7,lr}                   @ save  registres
    mov r2,#0                               @ counter length 
1:                                          @ loop length calculation 
    ldrb r1,[r0,r2]                         @ read octet start position + index 
    cmp r1,#0                               @ if 0 its over 
    addne r2,r2,#1                          @ else add 1 in the length 
    bne 1b                                  @ and loop 
                                            @ so here r2 contains the length of the message 
    mov r1,r0                               @ address message in r1 
    mov r0,#STDOUT                          @ code to write to the standard output Linux 
    mov r7, #WRITE                          @ code call system "write" 
    svc #0                                  @ call systeme 
    pop {r0,r1,r2,r7,lr}                    @ restaur registers */ 
    bx lr                                   @ return

Arturo

compareLists: function [a,b][
    loop 0..min @[size a, size b] 'i [
        if a\[i] < b\[i] -> return true
        if a\[i] > b\[i] -> return false
    ]
    return less? size a size b
]

alias.infix '<=> 'compareLists

do [
    print [1 2 1 3 2] <=> [1 2 0 4 4 0 0 0]
]

Output:

false

AutoHotkey

Works with: AutoHotkey_L

The function is overkill as we can just compare the list's ObjMaxIndex()

List1 := [1,2,1,3,2]
List2 := [1,2,0,4,4,0,0,0]
MsgBox % order(List1, List2)

order(L1, L2){
	return L1.MaxIndex() < L2.MaxIndex()
}

AWK

# syntax: GAWK -f ORDER_TWO_NUMERICAL_LISTS.AWK
BEGIN {
    split("1,2,1,5,2",list1,",")
    split("1,2,1,5,2,2",list2,",")
    split("1,2,3,4,5",list3,",")
    split("1,2,3,4,5",list4,",")
    x = compare_array(list1,list2) ? "<" : ">=" ; printf("list1%slist2\n",x)
    x = compare_array(list2,list3) ? "<" : ">=" ; printf("list2%slist3\n",x)
    x = compare_array(list3,list4) ? "<" : ">=" ; printf("list3%slist4\n",x)
    exit(0)
}
function compare_array(arr1,arr2,  ans,i) {
    ans = 0
    for (i=1; i<=length(arr1); i++) {
      if (arr1[i] != arr2[i]) {
        ans = 1
        break
      }
    }
    if (length(arr1) != length(arr2)) {
      ans = 1
    }
    return(ans)
}

Output:

list1<list2
list2<list3
list3>=list4

BASIC256

Translation of: FreeBASIC

arraybase 1
dim list1(5): dim list2(6): dim list3(5): dim list4(5)
list1 = {1, 2, 1, 5, 2}
list2 = {1, 2, 1, 5, 2, 2}
list3 = {1, 2, 3, 4, 5}
list4 = {1, 2, 3, 4, 5}

if Orden(list1[], list2[]) then print "list1 < list2" else print "list 1>= list2"
if Orden(list2[], list3[]) then print "list2 < list3" else print "list2 >= list3"
if Orden(list3[], list4[]) then print "list3 < list4" else print "list3 >= list4"
end

function Orden(listA[], listB[])
	i = 0
	l1 = listA[?]
	l2 = listB[?]
	while (listA[i] = listB[i]) and i < l1 and i < l2
		i = i + 1
	end	while
	if listA[?] < listB[?] then return True
	if listA[?] > listB[?] then return False
	return l1 < l2
end function

Output:

Igual que la entrada de BBC BASIC.

BBC BASIC

'Ordered before' means 'less than' (see talk page).

      DIM list1(4) : list1() = 1, 2, 1, 5, 2
      DIM list2(5) : list2() = 1, 2, 1, 5, 2, 2
      DIM list3(4) : list3() = 1, 2, 3, 4, 5
      DIM list4(4) : list4() = 1, 2, 3, 4, 5
      
      IF FNorder(list1(), list2()) PRINT "list1<list2" ELSE PRINT "list1>=list2"
      IF FNorder(list2(), list3()) PRINT "list2<list3" ELSE PRINT "list2>=list3"
      IF FNorder(list3(), list4()) PRINT "list3<list4" ELSE PRINT "list3>=list4"
      END
      
      DEF FNorder(list1(), list2())
      LOCAL i%, l1%, l2%
      l1% = DIM(list1(),1) : l2% = DIM(list2(),1)
      WHILE list1(i%) = list2(i%) AND i% < l1% AND i% < l2%
        i% += 1
      ENDWHILE
      IF list1(i%) < list2(i%) THEN = TRUE
      IF list1(i%) > list2(i%) THEN = FALSE
      = l1% < l2%

Output:

list1<list2
list2<list3
list3>=list4

Bracmat

When evaluating a sum or a product, Bracmat creates an expression with a canonical order, which happens to be compatible with the order defined in this task. In a pattern, only a sum or product on the left hand side (lhs) of the match (:) operator is evaluated. In the solution below we match a composition of the two function arguments into a sum of two terms with itself. If the match expression succeeds, the lhs must already have been in canonical order before evaluation, which means that the first argument is smaller than the second argument. In that case the function outputs FALSE. Notice that if the arguments are the same, evaluation of the sum produces the product of one of the terms and a factor two. This complicates the pattern a bit.

(  1 2 3 4 5:?List1
& 1 2 1 5 2 2:?List2
& 1 2 1 5 2:?List3
& 1 2 1 5 2:?List4
& Cat Elephant Rat Cat:?List5
& Cat Elephant Rat:?List6
& Cat Cat Elephant:?List7
& ( gt
  =   first second
    .   !arg:(?first,?second)
      &   out
        $ (     (.!first)+(.!second)
              : ((.!first)+(.!second)|2*(.!first))
            & FALSE
          | TRUE
          )
  )
& gt$(!List1,!List2)
& gt$(!List2,!List3)
& gt$(!List3,!List4)
& gt$(!List4,!List5)
& gt$(!List5,!List6)
& gt$(!List6,!List7)
);

Output:

TRUE
TRUE
FALSE
FALSE
TRUE
TRUE

C

int list_cmp(int *a, int la, int *b, int lb)
{
	int i, l = la;
	if (l > lb) l = lb;
	for (i = 0; i < l; i++) {
		if (a[i] == b[i]) continue;
		return (a[i] > b[i]) ? 1 : -1;
	}
	if (la == lb) return 0;
	return la > lb ? 1 : -1;
}

This funciton returns one of three states, not a boolean. One can define boolean comparisons, such as list_less_or_eq, based on it:

#define list_less_or_eq(a,b,c,d) (list_cmp(a,b,c,d) != 1)

C#

namespace RosettaCode.OrderTwoNumericalLists
{
    using System;
    using System.Collections.Generic;

    internal static class Program
    {
        private static bool IsLessThan(this IEnumerable<int> enumerable,
            IEnumerable<int> otherEnumerable)
        {
            using (
                IEnumerator<int> enumerator = enumerable.GetEnumerator(),
                    otherEnumerator = otherEnumerable.GetEnumerator())
            {
                while (true)
                {
                    if (!otherEnumerator.MoveNext())
                    {
                        return false;
                    }

                    if (!enumerator.MoveNext())
                    {
                        return true;
                    }

                    if (enumerator.Current == otherEnumerator.Current)
                    {
                        continue;
                    }

                    return enumerator.Current < otherEnumerator.Current;
                }
            }
        }

        private static void Main()
        {
            Console.WriteLine(
                new[] {1, 2, 1, 3, 2}.IsLessThan(new[] {1, 2, 0, 4, 4, 0, 0, 0}));
        }
    }
}

Output:

False

C++

The built-in comparison operators already do this:

#include <iostream>
#include <vector>

int main() {
  std::vector<int> a;
  a.push_back(1);
  a.push_back(2);
  a.push_back(1);
  a.push_back(3);
  a.push_back(2);
  std::vector<int> b;
  b.push_back(1);
  b.push_back(2);
  b.push_back(0);
  b.push_back(4);
  b.push_back(4);
  b.push_back(0);
  b.push_back(0);
  b.push_back(0);

  std::cout << std::boolalpha << (a < b) << std::endl; // prints "false"
  return 0;
}

clojure

(defn lex? [a b]
  (compare a b))

Common Lisp

(defun list< (a b)
  (cond ((not b) nil)
        ((not a) t)
        ((= (first a) (first b))
         (list< (rest a) (rest b)))
        (t (< (first a) (first b)))))

Alternate version

(defun list< (a b)
  (let ((x (find-if-not #'zerop (mapcar #'- a b))))
    (if x (minusp x) (< (length a) (length b)))))

D

The built-in comparison operators already do this:

void main() {
    assert([1,2,1,3,2] >= [1,2,0,4,4,0,0,0]);
}

Delphi

Library: System.SysUtils

Library: System.Generics.Defaults

Translation of: Java

This is not a full translate of Java, just adaptation and aplication of method previus introduced.

program Order_two_numerical_lists;

{$APPTYPE CONSOLE}

uses
  System.SysUtils,
  System.Generics.Defaults;

type
  TArray = record
    class function LessOrEqual<T>(first, second: TArray<T>): Boolean; static;
  end;

class function TArray.LessOrEqual<T>(first, second: TArray<T>): Boolean;
begin
  if Length(first) = 0 then
    exit(true);
  if Length(second) = 0 then
    exit(false);
  var comp := TComparer<T>.Default.Compare(first[0], second[0]);
  if comp = 0 then
    exit(LessOrEqual(copy(first, 1, length(first)), copy(second, 1, length(second))));
  Result := comp < 0;
end;

begin
  writeln(TArray.LessOrEqual<Integer>([1, 2, 3], [2, 3, 4]));
  writeln(TArray.LessOrEqual<Integer>([2, 3, 4], [1, 2, 3]));
  writeln(TArray.LessOrEqual<Integer>([1, 2], [1, 2, 3]));
  writeln(TArray.LessOrEqual<Integer>([1, 2, 3], [1, 2]));
  writeln(TArray.LessOrEqual<Char>(['a', 'c', 'b'], ['a', 'b', 'b']));
  writeln(TArray.LessOrEqual<string>(['this', 'is', 'a', 'test'], ['this', 'is',
    'not', 'a', 'test']));
  readln;
end.

Output:

TRUE
FALSE
TRUE
FALSE
FALSE
TRUE

EasyLang

Translation of: C

func listcmp a[] b[] .
   for i to lower len a[] len b[]
      if a[i] < b[i]
         return -1
      elif a[i] > b[i]
         return 1
      .
   .
   if len a[] < len b[]
      return -1
   elif len a[] > len b[]
      return 1
   .
   return 0
.
print listcmp [ 2 4 5 ] [ 2 3 1 ]
print listcmp [ 2 3 1 ] [ 2 3 1 ]
print listcmp [ 2 3 1 ] [ 2 3 1 3 ]

Ela

[] <. _ = true
_ <. [] = false
(x::xs) <. (y::ys) | x == y = xs <. ys
                   | else   = x < y

[1,2,1,3,2] <. [1,2,0,4,4,0,0,0]

Elixir

The built-in comparison functions already do this (not only for lists of numbers, but for any arbitrary data type).

iex(1)> [1,2,3] < [1,2,3,4]
true
iex(2)> [1,2,3] < [1,2,4]
true

Erlang

Builtin. Example use from Erlang shell:

5> [1,2,3] < [1,2,3,4].
true
6> [1,2,3] < [1,2,4].  
true

F#

By using the Collection.Seq Module the static method Seq.compareWith fits our needs.

let inline cmp x y = if x < y then -1 else if x = y then 0 else 1
let before (s1 : seq<'a>) (s2 : seq<'a>) = (Seq.compareWith cmp s1 s2) < 0

[
    ([0], []);
    ([], []);
    ([], [0]);
    ([-1], [0]);
    ([0], [0]);
    ([0], [-1]);
    ([0], [0; -1]);
    ([0], [0; 0]);
    ([0], [0; 1]);
    ([0; -1], [0]);
    ([0; 0], [0]);
    ([0; 0], [1]);
]
|> List.iter (fun (x, y) -> printf "%A %s %A\n" x (if before x y then "< " else ">=") y)

Output:

[0] >= []
[] >= []
[] <  [0]
[-1] <  [0]
[0] >= [0]
[0] >= [-1]
[0] <  [0; -1]
[0] <  [0; 0]
[0] <  [0; 1]
[0; -1] >= [0]
[0; 0] >= [0]
[0; 0] <  [1]

Factor

All sequences respond to words in the math.order vocabulary.

IN: scratchpad { 2 3 } { 2 5 } before? .
t

FreeBASIC

Translation of: BBC BASIC

Dim Shared list1(4) As Integer = {1, 2, 1, 5, 2}
Dim Shared list2(5) As Integer = {1, 2, 1, 5, 2, 2}
Dim Shared list3(4) As Integer = {1, 2, 3, 4, 5}
Dim Shared list4(4) As Integer = {1, 2, 3, 4, 5}

Function Orden(listA() As Integer, listB() As Integer) As Boolean
    Dim As Integer i = 0, l1, l2
    l1 = Ubound(listA, 1) 
    l2 = Ubound(listB, 1)
    While listA(i) = listB(i) And i < l1 And i < l2
        i += 1
    Wend
    If listA(i) < listB(i) Then Return True
    If listA(i) > listB(i) Then Return False
    Return l1 < l2
End Function

If Orden(list1(), list2()) Then Print "list1<list2" Else Print "list1>=list2"
If Orden(list2(), list3()) Then Print "list2<list3" Else Print "list2>=list3"
If Orden(list3(), list4()) Then Print "list3<list4" Else Print "list3>=list4"

Sleep

Output:

Igual que la entrada de BBC BASIC.

Go

package main

import "fmt"

// If your numbers happen to be in the range of Unicode code points (0 to 0x10ffff), this function
// satisfies the task:
func lessRune(a, b []rune) bool {
    return string(a) < string(b) // see also bytes.Compare
}

// Otherwise, the following function satisfies the task for all integer
// and floating point types, by changing the type definition appropriately.
type numericType int

func lessNT(a, b []numericType) bool {
    l := len(a)
    if len(b) < l {
        l = len(b)
    }
    for i := 0; i < l; i++ {
        if a[i] != b[i] {
            return a[i] < b[i]
        }
    }
    return l < len(b)
}

var testCases = [][][]numericType{
    {{0}, {}},
    {{}, {}},
    {{}, {0}},

    {{-1}, {0}},
    {{0}, {0}},
    {{0}, {-1}},

    {{0}, {0, -1}},
    {{0}, {0, 0}},
    {{0}, {0, 1}},
    {{0, -1}, {0}},
    {{0, 0}, {0}},
    {{0, 0}, {1}},
}

func main() {
    // demonstrate the general function
    for _, tc := range testCases {
        fmt.Printf("order %6s before %6s : %t\n",
            fmt.Sprintf("%v", tc[0]),
            fmt.Sprintf("%v", tc[1]),
            lessNT(tc[0], tc[1]))
    }
    fmt.Println()

    // demonstrate that the byte specific function gives identical results
    // by offsetting test data to a printable range of characters.
    for _, tc := range testCases {
        a := toByte(tc[0])
        b := toByte(tc[1])
        fmt.Printf("order %6q before %6q : %t\n",
            string(a),
            string(b),
            lessByte(a, b))
    }
}

func toByte(a []numericType) []byte {
    b := make([]byte, len(a))
    for i, n := range a {
        b[i] = 'b' + byte(n)
    }
    return b
}

Output:

order    [0] before     [] : false
order     [] before     [] : false
order     [] before    [0] : true
order   [-1] before    [0] : true
order    [0] before    [0] : false
order    [0] before   [-1] : false
order    [0] before [0 -1] : true
order    [0] before  [0 0] : true
order    [0] before  [0 1] : true
order [0 -1] before    [0] : false
order  [0 0] before    [0] : false
order  [0 0] before    [1] : true

order    "b" before     "" : false
order     "" before     "" : false
order     "" before    "b" : true
order    "a" before    "b" : true
order    "b" before    "b" : false
order    "b" before    "a" : false
order    "b" before   "ba" : true
order    "b" before   "bb" : true
order    "b" before   "bc" : true
order   "ba" before    "b" : false
order   "bb" before    "b" : false
order   "bb" before    "c" : true

Groovy

Solution:

class CList extends ArrayList implements Comparable {
    CList() { }
    CList(Collection c) { super(c) }
    int compareTo(Object that) {
        assert that instanceof List
        def n = [this.size(), that.size()].min()
        def comp = [this[0..<n], that[0..<n]].transpose().find { it[0] != it[1] }
        comp ? comp[0] <=> comp[1] : this.size() <=> that.size()
    }
}

Test:

CList a, b; (a, b) = [[], []]; assert ! (a < b)
b = [1] as CList;              assert   (a < b)
a = [1] as CList;              assert ! (a < b)
b = [2] as CList;              assert   (a < b)
a = [2, -1, 0] as CList;       assert ! (a < b)
b = [2, -1] as CList;          assert ! (a < b)
b = [2, -1, 0] as CList;       assert ! (a < b)
b = [2, -1, 0, -17] as CList;  assert   (a < b)
a = [2,  8, 0] as CList;       assert ! (a < b)

Haskell

The built-in comparison operators already do this:

Prelude>  [1,2,1,3,2] < [1,2,0,4,4,0,0,0]
False

Icon and Unicon

List_llt is written in the style of all Icon/Unicon relational operators returning its right argument if successful and signaling failure otherwise.

procedure main()
   write( if list_llt([1,2,1,3,2],[1,2,0,4,4,0,0,0]) then "true" else "false" ) 
end


procedure list_llt(L1,L2)  #: returns L2 if L1 lexically lt L2 or fails
every i := 1 to min(*L1,*L2) do
   if L1[i] << L2[i] then return L2 
   else if L1[i] >> L2[i] then fail
if *L1 < *L2 then return L2
end

J

J's built-in comparator operates element-wise. To compare general sequences you can either box them and use sort. Or for numeric sequences append minus infinity and sort. However numeric scalars sort ahead of vectors, i.e. are different from length one lists.

before=: -.@(-: /:~)@,&<~

cmp=: {.@\:@,:&(,&__)

Below demonstrates non-decreasing order cmp treats length one vector same as scalar

   cmp&.>"{~ ('';0;(,0);1;(,1);1 1)
┌─┬─┬─┬─┬─┬─┐
│0│1│1│1│1│1│
├─┼─┼─┼─┼─┼─┤
│0│0│0│1│1│1│
├─┼─┼─┼─┼─┼─┤
│0│0│0│1│1│1│
├─┼─┼─┼─┼─┼─┤
│0│0│0│0│0│1│
├─┼─┼─┼─┼─┼─┤
│0│0│0│0│0│1│
├─┼─┼─┼─┼─┼─┤
│0│0│0│0│0│0│
└─┴─┴─┴─┴─┴─┘

before&.>"{~ (0;1;'';(,0);(,1);1 1)
┌─┬─┬─┬─┬─┬─┐
│0│1│1│1│1│1│
├─┼─┼─┼─┼─┼─┤
│0│0│1│1│1│1│
├─┼─┼─┼─┼─┼─┤
│0│0│0│1│1│1│
├─┼─┼─┼─┼─┼─┤
│0│0│0│0│1│1│
├─┼─┼─┼─┼─┼─┤
│0│0│0│0│0│1│
├─┼─┼─┼─┼─┼─┤
│0│0│0│0│0│0│
└─┴─┴─┴─┴─┴─┘

Java

Works with: Java version 1.5+

Translation of: Common Lisp

There are a few methods here. The method named "ordered" which works on arrays is a translation of Common Lisp. The other two are loose translations of Tcl (some tweaks were needed to get the length checks to work out) and are probably better options.

import java.util.Arrays;
import java.util.List;

public class ListOrder{
	public static boolean ordered(double[] first, double[] second){
		if(first.length == 0) return true;
		if(second.length == 0) return false;
		if(first[0] == second[0])
			return ordered(Arrays.copyOfRange(first, 1, first.length),
					Arrays.copyOfRange(second, 1, second.length));
		return first[0] < second[0];
	}
	
	public static <T extends Comparable<? super T>> boolean ordered(List<T> first, List<T> second){
		int i = 0;
		for(; i < first.size() && i < second.size();i++){
			int cmp = first.get(i).compareTo(second.get(i));
			if(cmp == 0) continue;
			if(cmp < 0) return true;
			return false;
		}
		return i == first.size();
	}
	
	public static boolean ordered2(double[] first, double[] second){
		int i = 0;
		for(; i < first.length && i < second.length;i++){
			if(first[i] == second[i]) continue;
			if(first[i] < second[i]) return true;
			return false;
		}
		return i == first.length;
	}
}

JavaScript

ES6

<= is already defined for numeric lists in JavaScript

(() => {
    'use strict';

    // <= is already defined for lists in JS

    // compare :: [a] -> [a] -> Bool
    const compare = (xs, ys) => xs <= ys;


    // TEST
    return [
        compare([1, 2, 1, 3, 2], [1, 2, 0, 4, 4, 0, 0, 0]),
        compare([1, 2, 0, 4, 4, 0, 0, 0], [1, 2, 1, 3, 2])
    ];

    // --> [false, true]
})()

Output:

[false, true]

Joy

DEFINE order ==
[equal] [false]
[[[[size] dip size <=] [[<=] mapr2 true [and] fold]] [i] map i and]
ifte.

Using it:

[1 2] [1 2 3] order. # true
[1 2] [1 3] order.   # true
[1 2] [1 2] order.   # false
[1 3] [1 2] order.   # false
[1 2 3] [1 2] order. # false

jq

jq's builtin comparison operators use lexicographic ordering for arrays in general, not just arrays of integers.

[1,2,3] < [1,2,3,4]  # => true
[1,2,3] < [1,2,4]    # => true
[1,2,3] < [1,2,3]    # => false

Julia

Works with: Julia version 0.6

function islexless(a::AbstractArray{<:Real}, b::AbstractArray{<:Real})
    for (x, y) in zip(a, b)
        if x == y continue end
        return x < y
    end
    return length(a) < length(b)
end

using Primes, Combinatorics
tests = [[1, 2, 3], primes(10), 0:2:6, [-Inf, 0.0, Inf], [π, e, φ, catalan], [2015, 5], [-sqrt(50.0), 50.0 ^ 2]]
println("List not sorted:\n - ", join(tests, "\n - "))
sort!(tests; lt=islexless)
println("List sorted:\n - ", join(tests, "\n - "))

Output:

List not sorted:
 - [1, 2, 3]
 - [2, 3, 5, 7]
 - 0:2:6
 - [-Inf, 0.0, Inf]
 - [3.14159, 2.71828, 1.61803, 0.915966]
 - [2015, 5]
 - [-7.07107, 2500.0]
List sorted:
 - [-Inf, 0.0, Inf]
 - [-7.07107, 2500.0]
 - 0:2:6
 - [1, 2, 3]
 - [2, 3, 5, 7]
 - [3.14159, 2.71828, 1.61803, 0.915966]
 - [2015, 5]

Klingphix

include ..\Utilitys.tlhy

( 1 2 3 ) ( 1 2 3 4 ) less ?
( 1 2 3 4 ) ( 1 2 3 ) less ?
( 1 2 4 ) ( 1 2 3 ) less ?
( 1 2 3 ) ( 1 2 3 ) less ?
( 1 2 3 ) ( 1 2 4 ) less ?

"End " input

Kotlin

// version 1.0.6

operator fun <T> List<T>.compareTo(other: List<T>): Int
    where T: Comparable<T>, T: Number {
    for (i in 0 until this.size) {
        if (other.size == i) return 1
        when {
            this[i] < other[i] -> return -1
            this[i] > other[i] -> return 1
        }
    }
    return if (this.size == other.size) 0 else -1
} 

fun main(args: Array<String>) {
    val lists = listOf(
        listOf(1, 2, 3, 4, 5),
        listOf(1, 2, 1, 5, 2, 2),
        listOf(1, 2, 1, 5, 2),
        listOf(1, 2, 1, 5, 2),
        listOf(1, 2, 1, 3, 2),
        listOf(1, 2, 0, 4, 4, 0, 0, 0),
        listOf(1, 2, 0, 4, 4, 1, 0, 0)
    )
    for (i in 0 until lists.size) println("list${i + 1} : ${lists[i]}")
    println()  
    for (i in 0 until lists.size - 1) println("list${i + 1} > list${i + 2} = ${lists[i] > lists[i + 1]}")    
}

Output:

list1 : [1, 2, 3, 4, 5]
list2 : [1, 2, 1, 5, 2, 2]
list3 : [1, 2, 1, 5, 2]
list4 : [1, 2, 1, 5, 2]
list5 : [1, 2, 1, 3, 2]
list6 : [1, 2, 0, 4, 4, 0, 0, 0]
list7 : [1, 2, 0, 4, 4, 1, 0, 0]

list1 > list2 = true
list2 > list3 = true
list3 > list4 = false
list4 > list5 = true
list5 > list6 = true
list6 > list7 = false

LabVIEW

Translation of: AutoHotkey

This image is a VI Snippet, an executable image of LabVIEW code. The LabVIEW version is shown on the top-right hand corner. You can download it, then drag-and-drop it onto the LabVIEW block diagram from a file browser, and it will appear as runnable, editable code.

Lasso

This is built into the Lasso comparison operators

local(
	first = array(1,2,1,3,2),
	second = array(1,2,0,4,4,0,0,0),
)
#first < #second

local(
	first = array(1,1,1,3,2),
	second = array(1,2,0,4,4,0,0,0),
)
#first < #second

Output:

false
true

Lhogho

Uses standard '=' notation

print [1 2] = [1 2]
print [1 2] = [1 2 3]
print [1 3] = [1 2]
print [1 2 3] = [1 2]

make "list1 [1 2 3 4 5 6]
make "list2 [1 2 3 4 5 7]
print :list1 = :list2

Output:

true 
false 
false 
false 
false

Lua

In Lua tables with numerical indices are used as lists or arrays and they do not support comparison out-of-the-box, so a function is needed to implement the comparison:

function arraycompare(a, b)
    for i = 1, #a do
        if b[i] == nil then
            return true
        end
        if a[i] ~= b[i] then
            return a[i] < b[1]
        end
    end
    return true
end

Here is some demonstration code:

function randomarray()
    local t = {}
    for i = 1, math.random(1, 10) do
        t[i] = math.random(1, 10)
    end
    return t
end

math.randomseed(os.time())

for i = 1, 10 do
    local a = randomarray()
    local b = randomarray()

    print(
        string.format("{%s} %s {%s}",
        table.concat(a, ', '),
        arraycompare(a, b) and "<=" or ">",
        table.concat(b, ', ')))
end

Output:

(time used as random seed

1413127434):

    {10, 7, 4, 9, 10, 3, 5, 5, 5, 5} > {7, 4, 6, 4, 3, 5, 10}
    {5, 7} <= {6, 3, 7, 7, 7, 1}
    {4} <= {10, 10, 3, 8, 10, 5, 2, 5, 10, 6}
    {6} <= {6, 10, 2, 1, 9, 4, 5, 6, 9}
    {9, 5, 7, 5, 5, 7, 9, 5, 6, 8} > {4, 7, 3, 5, 1, 2, 1, 2}
    {10, 8, 6, 1, 8, 5, 4} > {1, 2}
    {9, 7} > {4, 1, 5, 2, 6, 1, 9, 3, 5}
    {5, 9, 7, 6, 10, 8} <= {9, 6, 9}
    {4, 3, 4, 6, 3, 6, 7, 2, 2, 5} > {3, 10, 6, 8, 1}
    {1, 5, 1, 5, 4} > {1, 3, 5, 3, 2, 10, 1}

Maple

orderLists := proc(num1,num2)
	local len1, len2,i:
	len1,len2 := numelems(num1),numelems(num2):
	for i to min(len1,len2) do
		if num1[i] <> num2[i] then
			return evalb(num1[i]<num2[i]):
		end if:
	end do:
	return evalb(len1 < len2):
end proc:

Mathematica/Wolfram Language

order[List1_, List2_] := With[{
   L1 = List1[[1 ;; Min @@ Length /@ {List1, List2}]], 
   L2 = List2[[1 ;; Min @@ Length /@ {List1, List2}]] 
},
   If [Thread[Order[L1, L2]] == 0,
   Length[List1] < Length[List2],
   Thread[Order[L1, L2]] == 1
   ]]

Example use:
order[ {1, 2, 1, 3, 2}, {1, 2, 0, 4, 4, 0, 0, 0} ]
->False
order[ {1, 2}, {1, 2, 4, 4, 0, 0} ]
->True

Maxima

"<<"(a,b):=block([n:min(length(a),length(b))],
catch(for i thru n do (if a[i]#b[i] then throw(is(a[i]<b[i]))),
throw(is(length(a)<length(b)))))$
infix("<<")$

[1,2,3] << [1,2,4];
true

[1,2,3] << [1,2];
false

[1,2] << [1,2];
false

Mercury

For a particular numerical type, you can get away with

:- pred lt(list(int)::in, list(int)::in) is semidet.
lt([], [_|_]).
lt([H1|T1], [H2|T2]) :- H1 =< H2, T1 `lt` T2.

For a list of any numerical type, one way would be to use a typeclass:

:- pred lt(list(T)::in, list(T)::in) is semidet <= comparable(T).
lt([], [_|_]).
lt([H1|T1], [H2|T2]) :- H1 =< H2, T1 `lt` T2.

... which you would have to create:

:- module comparable.
:- interface.
:- import_module int, float, integer, list.

:- typeclass comparable(T) where [
        pred '<'(T::in, T::in) is semidet,
        pred '=<'(T::in, T::in) is semidet
].
:- instance comparable(int).
:- instance comparable(float).
:- instance comparable(integer).
:- instance comparable(list(T)) <= comparable(T).

:- implementation.

:- instance comparable(int) where [ 
        pred('<'/2) is int.(<),
        pred('=<'/2) is int.(=<) 
].
% likewise for float and integer...
:- instance comparable(list(T)) <= comparable(T) where [
        pred('<'/2) is lt,   % the 'lt' above.
        pred('=<'/2) is lte  % 'lt' with: lte([], []).
].

% pred lt
% pred lte

Which would be used in this way - note the typeclass and the comparison operator.

:- pred test(list(T), list(T), io, io) <= comparable(T).
:- mode test(in, in, di, uo) is det.
test(A, B) -->
        io.write(A), io.write_string(" < "), io.write(B),
        io.write_string(" : "), io.write_string(S), io.nl,
        { A < B -> S = "yes" ; S = "no" }.

Miranda

main :: [sys_message]
main = [Stdout (lay (map show [
             order [1,2,1,3,2] [1,2,0,4,4,0,0,0],
             order [1,2,0,4,4,0,0,0] [1,2,1,3,2]]))]

order :: [*]->[*]->bool
order as     []     = True
order []     as     = False
order (a:as) (b:bs) = a < b, if a ~= b
                    = order as bs, otherwise

Output:

False
True

Nim

proc `<`[T](a, b: openarray[T]): bool =
  for i in 0 .. min(a.len, b.len):
    if a[i] < b[i]: return true
    if a[i] > b[i]: return false
  return a.len < b.len

echo([1,2,1,3,2] < [1,2,0,4,4,0,0,0])

Output:

false

OCaml

The built-in comparison operators already do this for lists (although this is not documented):

# [1;2;1;3;2] < [1;2;0;4;4;0;0;0];;
- : bool = false

(Warning: However, the built-in comparison operators do not do this for arrays:

# [|1;2;1;3;2|] < [|1;2;0;4;4;0;0;0|];;
- : bool = true

)

But we could write it explicitly this way:

let rec ordered_lists = function
  | x1::tl1, x2::tl2 ->
      (match compare x1 x2 with
      | 0 -> ordered_lists (tl1, tl2)
      | 1 -> false
      | _ -> true)
  | [], _ -> true
  | _ -> false

Here is a small script to test this function:

(* copy-paste the code of ordered_lists here *)

let make_num_list p n =
  let rec aux acc =
    if Random.int p = 0 then acc
    else aux (Random.int n :: acc)
  in
  aux []

let print_num_list lst =
  List.iter (Printf.printf " %d") lst;
  print_newline()

let () =
  Random.self_init();
  let lst1 = make_num_list 8 5 in
  let lst2 = make_num_list 8 5 in
  print_num_list lst1;
  print_num_list lst2;
  Printf.printf "ordered: %B\n" (ordered_lists (lst1, lst2))

Sample execution:

$ ocaml ordered_lists.ml
 1 2 1 3 2
 1 2 0 4 4 0 0 0
ordered: false

Also notice that the function ordered_lists will work with anything the function Pervasives.compare is able to compare (most OCaml types and structures made from the base types). In the prototype of this function below 'a list means a list of anything:

val ordered_lists : 'a list * 'a list -> bool

Oforth

In Oforth, list comparison is already defined.

Output:

[1,2,0,4,4,0,0,0] [1,2,1,3,2] <= .
1 ok

Ol

This sample very similar to Scheme, but implements proper tail recursion. So can test unlimited length lists.

(define (lexorder a b)
   (cond
      ((null? b) #false)
      ((null? a) #true)
      ((< (car a) (car b)) #true)
      ((> (car a) (car b)) #false)
      (else
         (lexorder (cdr a) (cdr b)))))

(print (lexorder '(1 2 3) '(1 2 3 4))) ; => true
(print (lexorder '(1 2 4) '(1 2 3)))   ; => false
(print (lexorder '(1 2 3) '(1 2)))     ; => false
(print (lexorder '(1 2 3) '(1 2 3)))   ; => false
(print (lexorder '(1 2 3) '(1 2 8)))   ; => true

PARI/GP

lex(u,v)<1

Perl

use strict;
use warnings;

sub orderlists {
    my ($firstlist, $secondlist) = @_;

    my ($first, $second);
    while (@{$firstlist}) {
        $first = shift @{$firstlist};
        if (@{$secondlist}) {
            $second = shift @{$secondlist};
            if ($first < $second) {
                return 1;
            }
            if ($first > $second) {
                return 0;
            }
        }
        else {
            return 0;
        }
    }

    @{$secondlist} ? 1 : 0;
}

foreach my $pair (
    [[1, 2, 4], [1, 2, 4]],
    [[1, 2, 4], [1, 2,  ]],
    [[1, 2,  ], [1, 2, 4]],
    [[55,53,1], [55,62,83]],
    [[20,40,51],[20,17,78,34]],
) {
    my $first  = $pair->[0];
    my $second = $pair->[1];
    my $before = orderlists([@$first], [@$second]) ? 'true' : 'false';
    print "(@$first) comes before (@$second) : $before\n";
}

Output:

(1 2 4) comes before (1 2 4) : false
(1 2 4) comes before (1 2) : false
(1 2) comes before (1 2 4) : true
(55 53 1) comes before (55 62 83) : true
(20 40 51) comes before (20 17 78 34) : false

Phix

Handled natively, eg ("?" is the shorthand print operator)

with javascript_semantics
?{1,2,3}<{1,2,3,4}  -- 1 (true under p2js)
?{1,2,3,4}<{1,2,3}  -- 0 (false "")
?{1,2,4}<{1,2,3}    -- 0 (false "")
?{1,2,3}<{1,2,3}    -- 0 (false "")
?{1,2,3}<{1,2,4}    -- 1 (true "")

Elements can be any mix of integers, floating point numbers, strings, or nested subsequences, with atoms ordered before sequences.
If you want -1/0/+1 (instead of the true(1)/false(0) shown above), use the builtin compare() function, and that will match under p2js.

Phixmonti

Translation of: Phix

include Utilitys.pmt

def ? print nl enddef

( 1 2 3 ) ( 1 2 3 4 ) < ?
( 1 2 3 4 ) ( 1 2 3 ) < ?
( 1 2 4 ) ( 1 2 3 ) < ?
( 1 2 3 ) ( 1 2 3 ) < ?
( 1 2 3 ) ( 1 2 4 ) < ?

Picat

Picat has a built-in general comparison operator @<, which compares terms in lexicographic order (numeric lists as well as atoms, strings, variables, and structures).

go =>
  Tests = [
     [[1,2,3], [1,2,3]],
     [[1,2,3], [1,2,3,4]],
     [[1,2,2], [1,2,3]],
     [[1,2,4], [1,2,3]],
     [1..10  , 1..8],
     [[]     , []],
     [[]     , [1]],
     [[1]    , [] ],
     [[-1,2,3,6,5],[-1,2,3,5,6]],
     [[-1,2,3,-5,6],[-1,2,3,-6,5]]
  ],
  foreach([L1,L2] in Tests)
     printf("%w @< %w: %w\n",L1,L2,cond(L1 @< L2,true,false))
  end,
  nl.

In the Picat shell, the result is yes/no rather than true/false:

Picat> [1,2,3] @< [1,2,3]

no

Picat> [1,2,3] @< [1,2,3,4] 
 
yes

PicoLisp

The built-in comparison functions already do this (not only for lists of numbers, but for any arbitrary data type).

: (> (1 2 0 4 4 0 0 0) (1 2 1 3 2))
-> NIL

Pike

int(0..1) order_array(array a, array b)
{
  if (!sizeof(a)) return true;
  if (!sizeof(b)) return false;
  if (a[0] == b[0])
    return order_array(a[1..], b[1..]);
  return a[0] < b[0];
}

Pikes Array.sort_array() function can sort an array of arrays using the < operator, but it will sort longer arrays before shorter ones. Therefore the above function is still needed if the intent is to use the comparison for a sort operation.

If the numbers are in 32bit signed integer range, the following works too:

(string)a < (string)b;

PL/I

lists: procedure options (main);  /* 8 June 2014 */

   declare a(10) fixed initial (1, 2, 3, 4, 5, 8, 9, 10, 16, 17),
           b(15) fixed initial (5, 6, 7, 8, 9, 10, 11, 12, 15, 16, 17, 18, 20, 22, 23);

   put skip list (compare(a, b));
   put skip list (compare(b, a));
   put skip list (compare(a, a));


compare: procedure (a, b) returns (bit (1));
   declare (a, b)(*) fixed;
   declare (i, m, n) fixed binary;

   m = hbound(a,1); n = hbound(b,1);
   do i = 1 to min(m, n);
      return (a(i) < b(i));
   end;
   return (m < n);
end compare;

end lists;

Results:

'1'B    (true)
'0'B    (false)
'0'B

PowerShell

function  order($as,$bs) {
    if($as -and $bs) {
        $a, $as = $as
        $b, $bs = $bs
        if($a -eq $b) {order $as $bs}
        else{$a -lt $b}
    } elseif ($bs) {$true} else {$false}
}
"$(order @(1,2,1,3,2) @(1,2,0,4,4,0,0,0))"

Output:

False

Non-Recursive Version

function Test-Order ([int[]]$ReferenceArray, [int[]]$DifferenceArray)
{
    for ($i = 0; $i -lt $ReferenceArray.Count; $i++)
    { 
        if ($ReferenceArray[$i] -lt $DifferenceArray[$i])
        {
            return $true
        }
        elseif ($ReferenceArray[$i] -gt $DifferenceArray[$i])
        {
            return $false
        }
    }

    return ($ReferenceArray.Count -lt $DifferenceArray.Count) -or (Compare-Object $ReferenceArray $DifferenceArray) -eq $null
}

Test-Order -ReferenceArray 1, 2, 1, 3, 2 -DifferenceArray 1, 2, 0, 4, 4, 0, 0, 0
Test-Order -ReferenceArray 1, 2, 1, 3, 2 -DifferenceArray 1, 2, 2, 4, 4, 0, 0, 0
Test-Order -ReferenceArray 1, 2, 3       -DifferenceArray 1, 2
Test-Order -ReferenceArray 1, 2          -DifferenceArray 1, 2, 3
Test-Order -ReferenceArray 1, 2          -DifferenceArray 1, 2

Output:

False
True
False
True
True

PureBasic

DataSection
  Array_1:
  Data.i 5              ;element count
  Data.i 1, 2, 3, 4, 5  ;element data
  Array_2:
  Data.i 6
  Data.i 1, 2, 1, 5, 2, 2
  Array_3:
  Data.i 5
  Data.i 1, 2, 1, 5, 2
  Array_4:
  Data.i 5
  Data.i 1, 2, 1, 5, 2
  Array_5:
  Data.i 4
  Data.i 1, 2, 1, 6
  Array_6:
  Data.i 5
  Data.i 1, 2, 1, 6, 2
EndDataSection

#False = 0
#True = 1

;helper subrountine to initialize a dataset, *dataPtr points to the elementcount followed by the element data
Procedure initArrayData(Array a(1), *dataPtr)
  Protected elementCount = PeekI(*dataPtr)
  
  Dim a(elementCount - 1)
  For i = 0 To elementCount - 1
    *dataPtr + SizeOf(Integer)
    a(i) = PeekI(*dataPtr)
  Next
EndProcedure

;helper subroutine that returns 'True' or 'False' for a boolean input
Procedure.s booleanText(b) 
  If b: ProcedureReturn "True": EndIf
  ProcedureReturn "False"
EndProcedure
  
Procedure order(Array a(1), Array b(1))
  Protected len_a = ArraySize(a()), len_b = ArraySize(b()), elementIndex

  While elementIndex <= len_a And elementIndex <= len_b And a(elementIndex) = b(elementIndex)
    elementIndex + 1
  Wend
  
  If (elementIndex > len_a  And elementIndex <= len_b) Or (elementIndex <= len_b And a(elementIndex) <= b(elementIndex))
    ProcedureReturn #True
  EndIf
EndProcedure

Dim A_1(0): initArrayData(A_1(), ?Array_1)
Dim A_2(0): initArrayData(A_2(), ?Array_2)
Dim A_3(0): initArrayData(A_3(), ?Array_3)
Dim A_4(0): initArrayData(A_4(), ?Array_4)
Dim A_5(0): initArrayData(A_5(), ?Array_5)
Dim A_6(0): initArrayData(A_6(), ?Array_6)

If OpenConsole()
  PrintN(booleanText(order(A_1(), A_2()))) ;False
  PrintN(booleanText(order(A_2(), A_3()))) ;False
  PrintN(booleanText(order(A_3(), A_4()))) ;False
  PrintN(booleanText(order(A_4(), A_5()))) ;True
  PrintN(booleanText(order(A_5(), A_6()))) ;True
  
  Print(#crlf$ + #crlf$ + "Press ENTER to exit"): Input()
  CloseConsole()
EndIf

Output:

False
False
False
True
True

Python

The built-in comparison operators already do this:

>>> [1,2,1,3,2] < [1,2,0,4,4,0,0,0]
False

Quackery

  [ [ over [] = iff false done
      dup  [] = iff true done
      behead rot behead rot
      2dup = iff 
        [ 2drop swap ] again
      > ]
    unrot 2drop ]               is []< ( [ [ --> b )

 ' [ [ ] [ 1 ] [ 1 1 1 ] [ 1 2 ] [ 1 2 1 ] [ 2 ] [ 2 1 ] [ 2 1 1 ] ]

shuffle sortwith []< echo

Output:

[ [ ] [ 1 ] [ 1 1 1 ] [ 1 2 ] [ 1 2 1 ] [ 2 ] [ 2 1 ] [ 2 1 1 ] ]

Racket

#lang racket

(define (lex<? a b)
  (cond ((null? b) #f)
        ((null? a) #t)
        ((= (car a) (car b)) (lex<? (cdr a) (cdr b)))
        (else (< (car a) (car b)))))

(lex<? '(1 2 3 4 5) '(1 2 3 4 4)) ; -> #f

Raku

(formerly Perl 6) There is already a built-in comparison operator.

my @a = <1 2 4>;
my @b = <1 2 4>;
say @a," before ",@b," = ", @a before @b;

@a = <1 2 4>;
@b = <1 2>;
say @a," before ",@b," = ", @a before @b;

@a = <1 2>;
@b = <1 2 4>;
say @a," before ",@b," = ", @a before @b;

for 1..10 {
    my @a = flat (^100).roll((2..3).pick);
    my @b = flat @a.map: { Bool.pick ?? $_ !! (^100).roll((0..2).pick) }
    say @a," before ",@b," = ", @a before @b;
}

Output:

1 2 4 before 1 2 4 = False
1 2 4 before 1 2 = False
1 2 before 1 2 4 = True
63 52 before 0 52 = False
17 75 24 before 31 75 24 = True
43 32 before 43 32 = False
73 84 before 2 84 = False
73 92 before 40 24 46 = False
16 24 before 41 24 = True
9 12 22 before 9 12 32 67 = True
81 23 before 81 23 = False
55 53 1 before 55 62 83 = True
20 40 51 before 20 17 78 34 = False

Rascal

The built-in comparison operator already does this:

rascal>[2,1,3] < [5,2,1,3]
bool: true

REXX

This REXX example uses the same lists as   BBC BASIC.

This example will also work with non-numeric strings.

/*REXX program determines  if  a list < previous list,   and returns   true  or  false. */
@.=;                    @.1 = 1 2 1 5 2
                        @.2 = 1 2 1 5 2 2
                        @.3 = 1 2 3 4 5
                        @.4 = 1 2 3 4 5
                                                 /* [↓]  compare a list to previous list*/
         do j=2  while  @.j\=='';      p= j - 1  /*P:  points to previous value in list.*/
         if FNorder(@.p, @.j)=='true'  then is= " < "       /*use a more familiar glyph.*/
                                       else is= " ≥ "       /* "  "   "      "      "   */
         say
         say right('['@.p"]", 40)  is  '['@.j"]"
         end   /*i*/
exit                                             /*stick a fork in it,  we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
FNorder: procedure;  parse arg x,y
         wx= words(x);     wy= words(y)
                                         do k=1  for min(wx, wy)
                                            a= word(x, k)         /*get a value from X. */
                                            b= word(y, k)         /* "  "   "     "  Y. */
                                         if a<b  then                return 'true'
                                                 else  if a>b  then  return 'false'
                                         end   /*k*/
         if wx<wy  then return 'true'                  /*handle case of equal (so far). */
                        return 'false'                 /*   "     "   "   "     "   "   */

output:

                             [1 2 1 5 2]  <  [1 2 1 5 2 2]

                           [1 2 1 5 2 2]  <  [1 2 3 4 5]

                             [1 2 3 4 5]  ≥  [1 2 3 4 5]

Ring

list1 = "1, 2, 1, 5, 2"
list2 = "5, 2, 1, 5, 2, 2"
list3 = "1, 2, 3, 4, 5"
list4 = "1, 2, 3, 4, 5"
 
if order(list1, list2) = 0 see "list1=list2" + nl
but order(list1, list2) < 0 see "list1<list2" + nl
else see "list1>list2" + nl ok

if order(list2, list3) = 0 see "list2=list3" + nl
but order(list2, list3) < 0 see "list2<list3" + nl
else see "list2>list3" + nl ok

if order(list3, list4) = 0 see "list3=list4" + nl
but order(list3, list4) < 0 see "list3<list4" + nl
else see "list3>list4" + nl ok
 
func order alist, blist
     return strcmp(alist, blist)

Output:

list1<list2
list2>list3
list3=list4

RPL

Works with: HP version 28

RPL code	Comment
≪ → a b ≪ a SIZE b SIZE MIN LAST < 1 ROT FOR j IF b j GET a j GET - THEN LAST 0 > SWAP DROP a SIZE 'j' STO END NEXT ≫ ≫ ‘GR8R?’ STO	GR8R? ( [reals] [reals] → boolean ) m = min(size(a),size(b)) ; res = (size(a)<size(b)) loop for j=1 to m if b[j]-a[j] ≠ 0 res = (b[j]-a[j]>0) break end if end loop, return res .

[1 2 1 5 2]    [1 2 1 5 2 2] GR8R?
[1 2 1 5 2 2]  [1 2 1 5 2] GR8R?
[1 2 1 5 2 2]  [1 2 3 4 5] GR8R?
[1 2 3 4 5]    [1 2 1 5 2 2] GR8R?
[1 2 3 4 5]    [1 2 3 4 5] GR8R?

Output:

5: 1
4: 0
3: 1
2: 0
1: 0

Ruby

The built-in <=> operator already does this:

>> ([1,2,1,3,2] <=> [1,2,0,4,4,0,0,0]) < 0
=> false

Rust

Vec<T> implements Ord when T does, so we can just compare them with <. (Same with arrays and slices).

vec![1, 2, 1, 3, 2] < vec![1, 2, 0, 4, 4, 0, 0, 0]

Scala

def lessThan1(a: List[Int], b: List[Int]): Boolean =
  if (b.isEmpty) false
  else if (a.isEmpty) true
  else if (a.head != b.head) a.head < b.head
  else lessThan1(a.tail, b.tail)

def lessThan2(a: List[Int], b: List[Int]): Boolean = (a, b) match {
  case (_, Nil) => false
  case (Nil, _) => true
  case (a :: _, b :: _) if a != b => a < b
  case _ => lessThan2(a.tail, b.tail)
}

def lessThan3(a: List[Int], b: List[Int]): Boolean =
  a.zipAll(b, Integer.MIN_VALUE, Integer.MIN_VALUE)
   .find{case (a, b) => a != b}
   .map{case (a, b) => a < b}
   .getOrElse(false)

val tests = List(
  (List(1, 2, 3), List(1, 2, 3)) -> false,
  (List(3, 2, 1), List(3, 2, 1)) -> false,
  (List(1, 2, 3), List(3, 2, 1)) -> true,
  (List(3, 2, 1), List(1, 2, 3)) -> false,
  (List(1, 2), List(1, 2, 3)) -> true,
  (List(1, 2, 3), List(1, 2)) -> false
)

tests.foreach{case test @ ((a, b), c) =>
  assert(lessThan1(a, b) == c, test)
  assert(lessThan2(a, b) == c, test)
  assert(lessThan3(a, b) == c, test)
}

Scheme

(define (lex<? a b)
        (cond ((null? b) #f)
              ((null? a) #t)
              ((= (car a) (car b)) (lex<? (cdr a) (cdr b)))
              (else (< (car a) (car b)))))

Seed7

The operator corresponding to the ordering described in this example is less than.

$ include "seed7_05.s7i";

const proc: main is func
  begin
    writeln([] (1)       < [] (1, 2));    # If the first list runs out of elements the result is TRUE.
    writeln([] (1, 2)    < [] (1));       # If the second list runs out of elements the result is FALSE.
    writeln([] (1, 2)    < [] (1, 2));    # If both lists run out of elements the result is FALSE.
    writeln([] (1, 2, 3) < [] (1, 1, 3)); # The second element is greater than --> FALSE
    writeln([] (1, 2, 3) < [] (1, 3, 3)); # The second element is less than --> TRUE
    writeln(0 times 0    < [] (1));       # The empty list is less than any nonempty list --> TRUE
    writeln([] (1)       < 0 times 0);    # Any nonempty list is not less than the empty list --> FALSE
    writeln(0 times 0    < 0 times 0);    # The empty list is not less than the empty list --> FALSE
  end func;

Output:

TRUE
FALSE
FALSE
FALSE
TRUE
TRUE
FALSE
FALSE

Sidef

Built-in, via the comparison operator (`<=>`):

func ordered(a, b) {
    (a <=> b) < 0
}

for p in [
    Pair([1,2,4], [1,2,4]),
    Pair([1,2,4], [1,2]  ),
    Pair([1,2],   [1,2,4]),
] {
    var a = p.first
    var b = p.second
    var before = ordered(a, b)
    say "#{a} comes before #{b} : #{before}"
}

Output:

[1, 2, 4] comes before [1, 2, 4] : false
[1, 2, 4] comes before [1, 2] : false
[1, 2] comes before [1, 2, 4] : true

Standard ML

- List.collate Int.compare ([1,2,1,3,2], [1,2,0,4,4,0,0,0]) = LESS;
val it = false : bool

Swift

let a = [1,2,1,3,2]
let b = [1,2,0,4,4,0,0,0]
println(lexicographicalCompare(a, b)) // this is "less than"

Output:

false

Tcl

proc numlist< {A B} {
    foreach a $A b $B {
        if {$a<$b} {
            return 1
        } elseif {$a>$b} {
            return 0
        }
    }
    return 0
}

TUSCRIPT

$$ MODE TUSCRIPT
MODE DATA
$$ numlists=*
1'2'1'3'2
1'2'0'4'4'0'0'0
1'2'3'4'5
1'2'1'5'2'2
1'2'1'6
1'2'1'6'2
1'2'4
1'2'4
1'2
1'2'4
$$ MODE TUSCRIPT
list1="1'2'5'6'7"
LOOP n,list2=numlists
text=CONCAT (" ",list1," < ",list2)
IF (list1<list2) THEN
PRINT " true: ",text
ELSE
PRINT "false: ",text
ENDIF
list1=VALUE(list2)
ENDLOOP

Output:

false:  1'2'5'6'7 < 1'2'1'3'2
false:  1'2'1'3'2 < 1'2'0'4'4'0'0'0
 true:  1'2'0'4'4'0'0'0 < 1'2'3'4'5
false:  1'2'3'4'5 < 1'2'1'5'2'2
 true:  1'2'1'5'2'2 < 1'2'1'6
 true:  1'2'1'6 < 1'2'1'6'2
 true:  1'2'1'6'2 < 1'2'4
false:  1'2'4 < 1'2'4
false:  1'2'4 < 1'2
 true:  1'2 < 1'2'4 

VBA

Private Function order(list1 As Variant, list2 As Variant) As Boolean
    i = 1
    Do While list1(i) <= list2(i)
        i = i + 1
        If i > UBound(list1) Then
            order = True
            Exit Function
        End If
        If i > UBound(list2) Then
            order = False
            Exit Function
        End If
    Loop
    order = False
End Function
Public Sub main()
    Debug.Print order([{1, 2, 3, 4}], [{1,2,0,1,2}])
    Debug.Print order([{1, 2, 3, 4}], [{1,2,3}])
    Debug.Print order([{1, 2, 3}], [{1,2,3,4}])
End Sub

Output:

Onwaar
Onwaar
Waar

VBScript

Function order_list(arr1,arr2)
	order_list = "FAIL"
	n1 = UBound(arr1): n2 = UBound(arr2)
	n = 0 : p = 0
	If n1 > n2 Then
		max = n2
	Else
		max = n1
	End If
	For i = 0 To max
		If arr1(i) > arr2(i) Then
			n = n + 1
		ElseIf arr1(i) = arr2(i) Then
			p = p + 1
		End If	
	Next
	If (n1 < n2 And n = 0) Or _
		 (n1 = n2 And n = 0 And p - 1 <> n1) Or _
		 (n1 > n2 And n = 0 And p = n2) Then
			order_list = "PASS"
	End If
End Function

WScript.StdOut.WriteLine order_list(Array(-1),Array(0))
WScript.StdOut.WriteLine order_list(Array(0),Array(0))
WScript.StdOut.WriteLine order_list(Array(0),Array(-1))
WScript.StdOut.WriteLine order_list(Array(0),Array(0,-1))
WScript.StdOut.WriteLine order_list(Array(0),Array(0,0))
WScript.StdOut.WriteLine order_list(Array(0),Array(0,1))
WScript.StdOut.WriteLine order_list(Array(0,-1),Array(0))
WScript.StdOut.WriteLine order_list(Array(0,0),Array(0))
WScript.StdOut.WriteLine order_list(Array(0,0),Array(1))
WScript.StdOut.WriteLine order_list(Array(1,2,1,3,2),Array(1,2,0,4,4,0,0,0))

Output:

PASS
FAIL
FAIL
PASS
PASS
PASS
FAIL
FAIL
PASS
FAIL

Wart

We'll simply overload < for lists.

def (a < b) :case (or list?.a list?.b)
  if not.b
       nil
     not.a
       b
     (car.a = car.b)
       (cdr.a < cdr.b)
     :else
       (car.a < car.b)

Output:

(< '(1 2 3) '(1 2 4))
=> 4
(< '(1 2 4) '(1 2 3))
=> nil

(< '(1 2 3) '(1 2 3 4))
=> (4)
(< '(1 2 4) '(1 2 3 4))
=> nil

Wren

var orderLists = Fn.new { |l1, l2|
    var len = (l1.count <= l2.count) ? l1.count : l2.count
    for (i in 0...len) {
        if (l1[i] < l2[i]) return true
        if (l1[i] > l2[i]) return false
    }
    return (l1.count < l2.count)
}

var lists = [
    [1, 2, 3, 4, 5],
    [1, 2, 1, 5, 2, 2],
    [1, 2, 1, 5, 2],
    [1, 2, 1, 5, 2],
    [1, 2, 1, 3, 2],
    [1, 2, 0, 4, 4, 0, 0, 0],
    [1, 2, 0, 4, 4, 1, 0, 0],
    [1, 2, 0, 4, 4, 1, 0, 1]
]

for (i in 0...lists.count) System.print("list[%(i)] : %(lists[i])")
System.print()
for (i in 0...lists.count-1) {
    var res = orderLists.call(lists[i], lists[i+1])
    System.print("list[%(i)] < list[%(i+1)] -> %(res)")
}

Output:

list[0] : [1, 2, 3, 4, 5]
list[1] : [1, 2, 1, 5, 2, 2]
list[2] : [1, 2, 1, 5, 2]
list[3] : [1, 2, 1, 5, 2]
list[4] : [1, 2, 1, 3, 2]
list[5] : [1, 2, 0, 4, 4, 0, 0, 0]
list[6] : [1, 2, 0, 4, 4, 1, 0, 0]
list[7] : [1, 2, 0, 4, 4, 1, 0, 1]

list[0] < list[1] -> false
list[1] < list[2] -> false
list[2] < list[3] -> false
list[3] < list[4] -> false
list[4] < list[5] -> false
list[5] < list[6] -> true
list[6] < list[7] -> true

XPL0

Translation of: ALGOL W

    \Compare lists (rows) of integers.
    \Returns TRUE if there is an element in A that is < the corresponding
    \ element in B and all previous elements are equal, FALSE otherwise.
    \The bounds of A and B should ALB :: AUB and BLB :: BUB.
    function ILT ( A, ALB, AUB, B, BLB, BUB );
    integer  A, ALB, AUB, B, BLB, BUB;
    integer  APos, BPos, Equal;
    begin
        APos := ALB;
        BPos := BLB;
        Equal := true;
        while APos <= AUB and BPos <= BUB and Equal do begin
            Equal := A( APos ) = B( BPos );
            if Equal then begin
                APos := APos + 1;
                BPos := BPos + 1
           end \if_Equal
        end; \while_more_elements_and_Equal
        if not Equal
        then \there is an element in A and B that is not Equal
             return A( APos ) < B( BPos )
        else \all elements are Equal or one list is shorter
             \A is < B if A has fewer elements
             return APos > AUB and BPos <= BUB
    end; \ILT

    \Tests A < B has the expected result
    procedure Test ( AName, A, ALB, AUB, BName, B, BLB, BUB, Expected );
    integer   AName, A, ALB, AUB, BName, B, BLB, BUB, Expected;
    integer   IsLt;
    begin
        IsLt := ILT( A, ALB, AUB, B, BLB, BUB );
        Text(0, AName);
        Text(0, if IsLt then " <  " else " >= ");
        Text(0, BName);
        Text(0, if IsLt = Expected then " " else ", NOT as expected");
        CrLf(0);
    end; \test

    integer List1, List2, List3, List4, List5, List6, List7, List8;
begin 
    \test cases as in the BBC basic sample
    List1 := [0, 1, 2, 1, 5, 2];
    List2 := [0, 1, 2, 1, 5, 2, 2];
    List3 := [0, 1, 2, 3, 4, 5];
    List4 := [0, 1, 2, 3, 4, 5];
    Test( "List1", List1, 1, 5, "List2", List2, 1, 6, true  );
    Test( "List2", List2, 1, 6, "List3", List3, 1, 5, true  );
    Test( "List3", List3, 1, 5, "List4", List4, 1, 5, false );
    \additional test cases
    List5 := [0, 9, 0, 2, 1, 0];
    List6 := [0, 4, 0, 7, 7];
    List7 := [0, 4, 0, 7];
    List8 := [0, 0];
    Test( "List5", List5, 1, 5, "List6", List6, 1, 4, false );
    Test( "List6", List6, 1, 4, "List7", List7, 1, 3, false );
    Test( "List7", List7, 1, 3, "List8", List8, 1, 0, false );
    Test( "List8", List8, 1, 0, "List7", List7, 1, 3, true  )
end

Output:

List1 <  List2 
List2 <  List3 
List3 >= List4 
List5 >= List6 
List6 >= List7 
List7 >= List8 
List8 <  List7 

Yabasic

Translation of: FreeBASIC

read num : dim list1(4)
read num : dim list2(5)
read num : dim list3(4)
read num : dim list4(4)

if Orden(list1(), list2()) then print "list1 < list2" else print "list1 >= list2" : fi
if Orden(list2(), list3()) then print "list2 < list3" else print "list2 >= list3" : fi
if Orden(list3(), list4()) then print "list3 < list4" else print "list3 >= list4" : fi
end

sub Orden(listA(), listB())
    i = 0
    l1 = arraysize(listA(), 1) 
    l2 = arraysize(listB(), 1)
    while listA(i) = listB(i) and i < l1 and i < l2
        i = i + 1
    wend
    if listA(i) < listB(i) then return True : fi
    if listA(i) > listB(i) then return False : fi
    return l1 < l2
end sub

data  1, 2, 1, 5, 2
data  1, 2, 1, 5, 2, 2
data  1, 2, 3, 4, 5
data  1, 2, 3, 4, 5

Output:

Igual que la entrada de BBC BASIC.

zkl

fcn listLT(a,b){
   a.walker().zip(b).filter1(fcn([(a,b)]){ a<b }) :  // lazy
   if(_) return(True);;
   a.len()<b.len()
}

Output:

listLT(T(1,2,3),T(2,3,4)).println();   //-->True
listLT(T(2,3,4),T(1,2,3)).println();   //-->False
listLT(T(1,2),T(1,2,3,4)).println();   //-->True
listLT(T(1,2,3,4),T(1,2,3)).println(); //-->False
listLT(T(1,2,3),T(1,2,3)).println();   //-->False