Sorting algorithms/Comb sort
You are encouraged to solve this task according to the task description, using any language you may know.
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:
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
- Task
Implement a comb sort.
The Comb Sort is a variant of the Bubble Sort.
Like the Shell sort, the Comb Sort increases the gap used in comparisons and exchanges.
Dividing the gap by works best, but 1.3 may be more practical.
Some implementations use the insertion sort once the gap is less than a certain amount.
- Also see
- the Wikipedia article: Comb sort.
Variants:
- Combsort11 makes sure the gap ends in (11, 8, 6, 4, 3, 2, 1), which is significantly faster than the other two possible endings.
- Combsort with different endings changes to a more efficient sort when the data is almost sorted (when the gap is small). Comb sort with a low gap isn't much better than the Bubble Sort.
Pseudocode:
function combsort(array input)
gap := input.size //initialize gap size
loop until gap = 1 and swaps = 0
//update the gap value for a next comb. Below is an example
gap := int(gap / 1.25)
if gap < 1
//minimum gap is 1
gap := 1
end if
i := 0
swaps := 0 //see Bubble Sort for an explanation
//a single "comb" over the input list
loop until i + gap >= input.size //see Shell sort for similar idea
if input[i] > input[i+gap]
swap(input[i], input[i+gap])
swaps := 1 // Flag a swap has occurred, so the
// list is not guaranteed sorted
end if
i := i + 1
end loop
end loop
end function
11l
<lang 11l>F combsort(&input)
V gap = input.len
V swaps = 1B
L gap > 1 | swaps
gap = max(1, Int(gap / 1.25))
swaps = 0B
L(i) 0 .< input.len - gap
V j = i + gap
I input[i] > input[j]
swap(&input[i], &input[j])
swaps = 1B
V y = [88, 18, 31, 44, 4, 0, 8, 81, 14, 78, 20, 76, 84, 33, 73, 75, 82, 5, 62, 70] combsort(&y) assert(y == sorted(y)) print(y)</lang>
- Output:
[0, 4, 5, 8, 14, 18, 20, 31, 33, 44, 62, 70, 73, 75, 76, 78, 81, 82, 84, 88]
360 Assembly
Translation from prototype.
The program uses ASM structured macros and two ASSIST macros to keep the code as short as possible.
<lang 360asm>* Comb sort 23/06/2016
COMBSORT CSECT
USING COMBSORT,R13 base register
B 72(R15) skip savearea
DC 17F'0' savearea
STM R14,R12,12(R13) prolog
ST R13,4(R15) "
ST R15,8(R13) "
LR R13,R15 "
L R2,N n
BCTR R2,0 n-1
ST R2,GAP gap=n-1
DO UNTIL=(CLC,GAP,EQ,=F'1',AND,CLI,SWAPS,EQ,X'00') repeat
L R4,GAP gap |
MH R4,=H'100' gap*100 |
SRDA R4,32 . |
D R4,=F'125' /125 |
ST R5,GAP gap=int(gap/1.25) |
IF CLC,GAP,LT,=F'1' if gap<1 then -----------+ |
MVC GAP,=F'1' gap=1 | |
ENDIF , end if <-----------------+ |
MVI SWAPS,X'00' swaps=false |
LA RI,1 i=1 |
DO UNTIL=(C,R3,GT,N) do i=1 by 1 until i+gap>n ---+ |
LR R7,RI i | |
SLA R7,2 . | |
LA R7,A-4(R7) r7=@a(i) | |
LR R8,RI i | |
A R8,GAP i+gap | |
SLA R8,2 . | |
LA R8,A-4(R8) r8=@a(i+gap) | |
L R2,0(R7) temp=a(i) | |
IF C,R2,GT,0(R8) if a(i)>a(i+gap) then ---+ | |
MVC 0(4,R7),0(R8) a(i)=a(i+gap) | | |
ST R2,0(R8) a(i+gap)=temp | | |
MVI SWAPS,X'01' swaps=true | | |
ENDIF , end if <-----------------+ | |
LA RI,1(RI) i=i+1 | |
LR R3,RI i | |
A R3,GAP i+gap | |
ENDDO , end do <---------------------+ |
ENDDO , until gap=1 and not swaps <------+
LA R3,PG pgi=0
LA RI,1 i=1
DO WHILE=(C,RI,LE,N) do i=1 to n -------+
LR R1,RI i |
SLA R1,2 . |
L R2,A-4(R1) a(i) |
XDECO R2,XDEC edit a(i) |
MVC 0(4,R3),XDEC+8 output a(i) |
LA R3,4(R3) pgi=pgi+4 |
LA RI,1(RI) i=i+1 |
ENDDO , end do <-----------+
XPRNT PG,L'PG print buffer
L R13,4(0,R13) epilog
LM R14,R12,12(R13) "
XR R15,R15 "
BR R14 exit
A DC F'4',F'65',F'2',F'-31',F'0',F'99',F'2',F'83',F'782',F'1'
DC F'45',F'82',F'69',F'82',F'104',F'58',F'88',F'112',F'89',F'74'
N DC A((N-A)/L'A) number of items of a GAP DS F gap SWAPS DS X flag for swaps PG DS CL80 output buffer XDEC DS CL12 temp for edit
YREGS
RI EQU 6 i
END COMBSORT</lang>
- Output:
-31 0 1 2 2 4 45 58 65 69 74 82 82 83 88 89 99 104 112 782
AArch64 Assembly
<lang AArch64 Assembly> /* ARM assembly AARCH64 Raspberry PI 3B */ /* program combSort64.s */
/*******************************************/ /* Constantes file */ /*******************************************/ /* for this file see task include a file in language AArch64 assembly */ .include "../includeConstantesARM64.inc"
/*********************************/ /* Initialized data */ /*********************************/ .data szMessSortOk: .asciz "Table sorted.\n" szMessSortNok: .asciz "Table not sorted !!!!!.\n" sMessResult: .asciz "Value : @ \n" szCarriageReturn: .asciz "\n"
.align 4
- TableNumber: .quad 1,3,6,2,5,9,10,8,4,7
TableNumber: .quad 10,9,8,7,6,-5,4,3,2,1
.equ NBELEMENTS, (. - TableNumber) / 8
/*********************************/ /* UnInitialized data */ /*********************************/ .bss sZoneConv: .skip 24 /*********************************/ /* code section */ /*********************************/ .text .global main main: // entry of program
ldr x0,qAdrTableNumber // address number table mov x1,0 mov x2,NBELEMENTS // number of élements bl combSort ldr x0,qAdrTableNumber // address number table bl displayTable ldr x0,qAdrTableNumber // address number table mov x1,NBELEMENTS // number of élements bl isSorted // control sort cmp x0,1 // sorted ? beq 1f ldr x0,qAdrszMessSortNok // no !! error sort bl affichageMess b 100f
1: // yes
ldr x0,qAdrszMessSortOk bl affichageMess
100: // standard end of the program
mov x0,0 // return code mov x8,EXIT // request to exit program svc 0 // perform the system call
qAdrsZoneConv: .quad sZoneConv qAdrszCarriageReturn: .quad szCarriageReturn qAdrsMessResult: .quad sMessResult qAdrTableNumber: .quad TableNumber qAdrszMessSortOk: .quad szMessSortOk qAdrszMessSortNok: .quad szMessSortNok /******************************************************************/ /* control sorted table */ /******************************************************************/ /* x0 contains the address of table */ /* x1 contains the number of elements > 0 */ /* x0 return 0 if not sorted 1 if sorted */ isSorted:
stp x2,lr,[sp,-16]! // save registers stp x3,x4,[sp,-16]! // save registers mov x2,0 ldr x4,[x0,x2,lsl 3]
1:
add x2,x2,1 cmp x2,x1 bge 99f ldr x3,[x0,x2, lsl 3] cmp x3,x4 blt 98f mov x4,x3 b 1b
98:
mov x0,0 // not sorted b 100f
99:
mov x0,1 // sorted
100:
ldp x3,x4,[sp],16 // restaur 2 registers ldp x2,lr,[sp],16 // restaur 2 registers ret // return to address lr x30
/******************************************************************/ /* comb sort */ /******************************************************************/ /* x0 contains the address of table */ /* x1 contains the first element */ /* x2 contains the number of element */ /* this routine use à factor to 1.28 see wikipedia for best factor */ combSort:
stp x1,lr,[sp,-16]! // save registers stp x2,x3,[sp,-16]! // save registers stp x4,x5,[sp,-16]! // save registers stp x6,x7,[sp,-16]! // save registers stp x8,x9,[sp,-16]! // save registers sub x9,x2,x1 // compute gap sub x2,x2,1 // compute end index n - 1 mov x7,100
1: // start loop 1
mul x9,x7,x9 // gap multiply by 100 lsr x9,x9,7 // divide by 128 cmp x9,0 mov x3,1 csel x9,x9,x3,ne mov x3,x1 // start index mov x8,0 // swaps
2: // start loop 2
add x4,x3,x9 // add gap to indice cmp x4,x2 bgt 4f ldr x5,[x0,x3,lsl 3] // load value A[j] ldr x6,[x0,x4,lsl 3] // load value A[j+1] cmp x6,x5 // compare value bge 3f str x6,[x0,x3,lsl 3] // if smaller inversion str x5,[x0,x4,lsl 3] mov x8,1 // swaps
3:
add x3,x3,1 // increment index j b 2b
4:
//bl displayTable cmp x9,1 // gap = 1 ? bne 1b // no loop cmp x8,1 // swaps ? beq 1b // yes -> loop 1
100:
ldp x8,x9,[sp],16 // restaur 2 registers ldp x6,x7,[sp],16 // restaur 2 registers ldp x4,x5,[sp],16 // restaur 2 registers ldp x2,x3,[sp],16 // restaur 2 registers ldp x1,lr,[sp],16 // restaur 2 registers ret // return to address lr x30
/******************************************************************/ /* Display table elements */ /******************************************************************/ /* x0 contains the address of table */ displayTable:
stp x1,lr,[sp,-16]! // save registers stp x2,x3,[sp,-16]! // save registers mov x2,x0 // table address mov x3,0
1: // loop display table
ldr x0,[x2,x3,lsl 3] ldr x1,qAdrsZoneConv bl conversion10S // décimal conversion ldr x0,qAdrsMessResult ldr x1,qAdrsZoneConv bl strInsertAtCharInc // insert result at @ character bl affichageMess // display message add x3,x3,1 cmp x3,NBELEMENTS - 1 ble 1b ldr x0,qAdrszCarriageReturn bl affichageMess mov x0,x2
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" </lang>
ActionScript
<lang ActionScript>function combSort(input:Array) { var gap:uint = input.length; var swapped:Boolean = false; while(gap > 1 || swapped) { gap /= 1.25; swapped = false; for(var i:uint = 0; i + gap < input.length; i++) { if(input[i] > input[i+gap]) { var tmp = input[i]; input[i] = input[i+gap]; input[i+gap]=tmp; swapped = true; } } } return input; }</lang>
Ada
<lang Ada>with Ada.Text_IO; procedure Comb_Sort is
generic
type Element_Type is private;
type Index_Type is range <>;
type Array_Type is array (Index_Type range <>) of Element_Type;
with function ">" (Left, Right : Element_Type) return Boolean is <>;
with function "+" (Left : Index_Type; Right : Natural) return Index_Type is <>;
with function "-" (Left : Index_Type; Right : Natural) return Index_Type is <>;
procedure Comb_Sort (Data: in out Array_Type);
procedure Comb_Sort (Data: in out Array_Type) is
procedure Swap (Left, Right : in Index_Type) is
Temp : Element_Type := Data(Left);
begin
Data(Left) := Data(Right);
Data(Right) := Temp;
end Swap;
Gap : Natural := Data'Length;
Swap_Occured : Boolean;
begin
loop
Gap := Natural (Float(Gap) / 1.25 - 0.5);
if Gap < 1 then
Gap := 1;
end if;
Swap_Occured := False;
for I in Data'First .. Data'Last - Gap loop
if Data (I) > Data (I+Gap) then
Swap (I, I+Gap);
Swap_Occured := True;
end if;
end loop;
exit when Gap = 1 and not Swap_Occured;
end loop;
end Comb_Sort;
type Integer_Array is array (Positive range <>) of Integer; procedure Int_Comb_Sort is new Comb_Sort (Integer, Positive, Integer_Array); Test_Array : Integer_Array := (1, 3, 256, 0, 3, 4, -1);
begin
Int_Comb_Sort (Test_Array);
for I in Test_Array'Range loop
Ada.Text_IO.Put (Integer'Image (Test_Array (I)));
end loop;
Ada.Text_IO.New_Line;
end Comb_Sort;</lang>
Output:
-1 0 1 3 3 4 256
AppleScript
<lang applescript>-- Comb sort with insertion sort finish. -- Comb sort algorithm: Włodzimierz Dobosiewicz and Artur Borowy, 1980. Stephen Lacey and Richard Box, 1991.
on combSort(theList, l, r) -- Sort items l thru r of theLIst.
set listLen to (count theList)
if (listLen < 2) then return
-- Negative and/or transposed range indices.
if (l < 0) then set l to listLen + l + 1
if (r < 0) then set r to listLen + r + 1
if (l > r) then set {l, r} to {r, l}
script o
property lst : theList
end script
-- This implementation performs fastest with a comb gap divisor of 1.4
-- and the insertion sort taking over when the gap's down to 8 or less.
set divisor to 1.4
set gap to (r - l + 1) div divisor
repeat while (gap > 8)
repeat with i from l to (r - gap)
set j to i + gap
set lv to o's lst's item i
set rv to o's lst's item j
if (lv > rv) then
set o's lst's item i to rv
set o's lst's item j to lv
end if
end repeat
set gap to gap div divisor
end repeat
insertionSort(theList, l, r)
return -- nothing.
end combSort
on insertionSort(theList, l, r) -- Sort items l thru r of theList.
set listLength to (count theList)
if (listLength < 2) then return
if (l < 0) then set l to listLength + l + 1
if (r < 0) then set r to listLength + r + 1
if (l > r) then set {l, r} to {r, l}
script o
property lst : theList
end script
set highestSoFar to o's lst's item l
set rv to o's lst's item (l + 1)
if (highestSoFar > rv) then
set o's lst's item l to rv
else
set highestSoFar to rv
end if
repeat with j from (l + 2) to r
set rv to o's lst's item j
if (highestSoFar > rv) then
repeat with i from (j - 2) to l by -1
set lv to o's lst's item i
if (lv > rv) then
set o's lst's item (i + 1) to lv
else
set i to i + 1
exit repeat
end if
end repeat
set o's lst's item i to rv
else
set o's lst's item (j - 1) to highestSoFar
set highestSoFar to rv
end if
end repeat
set o's lst's item r to highestSoFar
return -- nothing.
end insertionSort
-- Demo: local aList set aList to {7, 56, 70, 22, 94, 42, 5, 25, 54, 90, 29, 65, 87, 27, 4, 5, 86, 8, 2, 30, 87, 12, 85, 86, 7} combSort(aList, 1, -1) -- Sort items 1 thru -1 of aList. aList</lang>
- Output:
<lang applescript>{2, 4, 5, 5, 7, 7, 8, 12, 22, 25, 27, 29, 30, 42, 54, 56, 65, 70, 85, 86, 86, 87, 87, 90, 94}</lang>
ARM Assembly
<lang ARM Assembly> /* ARM assembly Raspberry PI */ /* program combSort.s */
/* REMARK 1 : this program use routines in a include file see task Include a file language arm assembly for the routine affichageMess conversion10 see at end of this program the instruction include */
/* for constantes see task include a file in arm assembly */ /************************************/ /* Constantes */ /************************************/ .include "../constantes.inc"
/*********************************/ /* Initialized data */ /*********************************/ .data szMessSortOk: .asciz "Table sorted.\n" szMessSortNok: .asciz "Table not sorted !!!!!.\n" sMessResult: .asciz "Value : @ \n" szCarriageReturn: .asciz "\n"
.align 4
- TableNumber: .int 1,3,6,2,5,9,10,8,4,7
TableNumber: .int 10,9,8,7,6,5,4,3,2,1
.equ NBELEMENTS, (. - TableNumber) / 4
/*********************************/ /* UnInitialized data */ /*********************************/ .bss sZoneConv: .skip 24 /*********************************/ /* code section */ /*********************************/ .text .global main main: @ entry of program
1:
ldr r0,iAdrTableNumber @ address number table mov r1,#0 mov r2,#NBELEMENTS @ number of élements bl combSort ldr r0,iAdrTableNumber @ address number table bl displayTable ldr r0,iAdrTableNumber @ address number table mov r1,#NBELEMENTS @ number of élements bl isSorted @ control sort cmp r0,#1 @ sorted ? beq 2f ldr r0,iAdrszMessSortNok @ no !! error sort bl affichageMess b 100f
2: @ yes
ldr r0,iAdrszMessSortOk bl affichageMess
100: @ standard end of the program
mov r0, #0 @ return code mov r7, #EXIT @ request to exit program svc #0 @ perform the system call
iAdrszCarriageReturn: .int szCarriageReturn iAdrsMessResult: .int sMessResult iAdrTableNumber: .int TableNumber iAdrszMessSortOk: .int szMessSortOk iAdrszMessSortNok: .int szMessSortNok /******************************************************************/ /* control sorted table */ /******************************************************************/ /* r0 contains the address of table */ /* r1 contains the number of elements > 0 */ /* r0 return 0 if not sorted 1 if sorted */ isSorted:
push {r2-r4,lr} @ save registers
mov r2,#0
ldr r4,[r0,r2,lsl #2]
1:
add r2,#1 cmp r2,r1 movge r0,#1 bge 100f ldr r3,[r0,r2, lsl #2] cmp r3,r4 movlt r0,#0 blt 100f mov r4,r3 b 1b
100:
pop {r2-r4,lr}
bx lr @ return
/******************************************************************/ /* comb Sort */ /******************************************************************/ /* r0 contains the address of table */ /* r1 contains the first element */ /* r2 contains the number of element */ /* this routine use à factor to 1.28 see wikipedia for best factor */ combSort:
push {r1-r9,lr} @ save registers
sub r9,r2,r1 @ compute gap
sub r2,r2,#1 @ compute end index = n - 1
mov r7,#100
1: @ start loop 1
mul r9,r7,r9 @ gap multiply by 100 lsrs r9,#7 @ divide by 128 equi * 0,78125 equi divide by 1,28 moveq r9,#1 @ if gap = 0 -> gap = 1 mov r8,#0 @ swaps mov r3,r1 @ indice
2: @ start loop 2
add r4,r3,r9
cmp r4,r2 @ end ?
bgt 3f
ldr r5,[r0,r3,lsl #2] @ load value A[j]
ldr r6,[r0,r4,lsl #2] @ load value A[j+1]
cmp r6,r5 @ compare value
strlt r6,[r0,r3,lsl #2] @ if smaller inversion
strlt r5,[r0,r4,lsl #2]
movlt r8,#1 @ swaps = 1
add r3,#1 @ increment indice
b 2b @ loop 2
3:
@ bl displayTable cmp r9,#1 @ gap = 1 ? bne 1b cmp r8,#1 @ swaps ? beq 1b @ yes -> loop 1
100:
pop {r1-r9,lr}
bx lr @ return
/******************************************************************/ /* Display table elements */ /******************************************************************/ /* r0 contains the address of table */ displayTable:
push {r0-r3,lr} @ save registers
mov r2,r0 @ table address
mov r3,#0
1: @ loop display table
ldr r0,[r2,r3,lsl #2] ldr r1,iAdrsZoneConv @ bl conversion10S @ décimal conversion ldr r0,iAdrsMessResult ldr r1,iAdrsZoneConv @ insert conversion bl strInsertAtCharInc bl affichageMess @ display message add r3,#1 cmp r3,#NBELEMENTS - 1 ble 1b ldr r0,iAdrszCarriageReturn bl affichageMess
100:
pop {r0-r3,lr}
bx lr
iAdrsZoneConv: .int sZoneConv /***************************************************/ /* ROUTINES INCLUDE */ /***************************************************/ .include "../affichage.inc" </lang>
Arturo
<lang rebol>combSort: function [items][
a: new items gap: size a swapped: true
while [or? gap > 1 swapped][
gap: (gap * 10) / 13
if or? gap=9 gap=10 -> gap: 11
if gap<1 -> gap: 1
swapped: false
i: 0
loop gap..dec size items 'j [
if a\[i] > a\[j] [
tmp: a\[i]
a\[i]: a\[j]
a\[j]: tmp
swapped: true
]
i: i + 1
]
]
return a
]
print combSort [3 1 2 8 5 7 9 4 6]</lang>
- Output:
1 2 3 4 5 6 7 8 9
AutoHotkey
<lang autohotkey>List1 = 23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78 List2 = 88,18,31,44,4,0,8,81,14,78,20,76,84,33,73,75,82,5,62,70
List2Array(List1, "MyArray") CombSort("MyArray") MsgBox, % List1 "`n" Array2List("MyArray")
List2Array(List2, "MyArray") CombSort("MyArray") MsgBox, % List2 "`n" Array2List("MyArray")
- ---------------------------------------------------------------------------
CombSort(Array) { ; CombSort of Array %Array%, length = %Array%0
- ---------------------------------------------------------------------------
Gap := %Array%0
While Gap > 1 Or Swaps {
If (Gap > 1)
Gap := 4 * Gap // 5
i := Swaps := False
While (j := ++i + Gap) <= %Array%0 {
If (%Array%%i% > %Array%%j%) {
Swaps := True
%Array%%i% := (%Array%%j% "", %Array%%j% := %Array%%i%)
}
}
}
}
- ---------------------------------------------------------------------------
List2Array(List, Array) { ; creates an array from a comma separated list
- ---------------------------------------------------------------------------
global StringSplit, %Array%, List, `,
}
- ---------------------------------------------------------------------------
Array2List(Array) { ; returns a comma separated list from an array
- ---------------------------------------------------------------------------
Loop, % %Array%0
List .= (A_Index = 1 ? "" : ",") %Array%%A_Index%
Return, List
}</lang> Message (1) box shows:
23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78 12,14,23,24,24,31,35,38,46,51,57,57,58,76,78,89,92,95,97,99
Message (2) box shows:
88,18,31,44,4,0,8,81,14,78,20,76,84,33,73,75,82,5,62,70 0,4,5,8,14,18,20,31,33,44,62,70,73,75,76,78,81,82,84,88
AWK
<lang awk>function combsort( a, len, gap, igap, swap, swaps, i ) { gap = len swaps = 1
while( gap > 1 || swaps ) { gap /= 1.2473; if ( gap < 1 ) gap = 1 i = swaps = 0 while( i + gap < len ) { igap = i + int(gap) if ( a[i] > a[igap] ) { swap = a[i] a[i] = a[igap] a[igap] = swap swaps = 1 } i++; } } }
BEGIN { a[0] = 5 a[1] = 2 a[2] = 7 a[3] = -11 a[4] = 6 a[5] = 1
combsort( a, length(a) )
for( i=0; i<length(a); i++ ) print a[i] }</lang>
BBC BASIC
<lang BBC BASIC>DEF PROC_CombSort11(Size%)
gap%=Size% REPEAT
IF gap% > 1 THEN
gap%=gap% / 1.3
IF gap%=9 OR gap%=10 gap%=11
ENDIF
I% = 1
Finished%=TRUE
REPEAT
IF data%(I%) > data%(I%+gap%) THEN
SWAP data%(I%),data%(I%+gap%)
Finished% = FALSE
ENDIF
I%+=1
UNTIL I%+gap% > Size%
UNTIL gap%=1 AND Finished%
ENDPROC</lang>
C
Implementation of Combsort11. Its efficiency can be improved by just switching to Insertion sort when the gap size becomes less than 10. <lang c>void Combsort11(double a[], int nElements) {
int i, j, gap, swapped = 1; double temp;
gap = nElements;
while (gap > 1 || swapped == 1)
{
gap = gap * 10 / 13;
if (gap == 9 || gap == 10) gap = 11;
if (gap < 1) gap = 1;
swapped = 0;
for (i = 0, j = gap; j < nElements; i++, j++)
{
if (a[i] > a[j])
{
temp = a[i];
a[i] = a[j];
a[j] = temp;
swapped = 1;
}
}
}
}</lang>
C#
<lang csharp>using System;
namespace CombSort {
class Program
{
static void Main(string[] args)
{
int[] unsorted = new int[] { 3, 5, 1, 9, 7, 6, 8, 2, 4 };
Console.WriteLine(string.Join(",", combSort(unsorted)));
}
public static int[] combSort(int[] input)
{
double gap = input.Length;
bool swaps = true;
while (gap > 1 || swaps)
{
gap /= 1.247330950103979;
if (gap < 1) { gap = 1; }
int i = 0;
swaps = false;
while (i + gap < input.Length)
{
int igap = i + (int)gap;
if (input[i] > input[igap])
{
int swap = input[i];
input[i] = input[igap];
input[igap] = swap;
swaps = true;
}
i++;
}
}
return input;
}
}
}</lang>
C++
This is copied from the Wikipedia article. <lang cpp>template<class ForwardIterator> void combsort ( ForwardIterator first, ForwardIterator last ) {
static const double shrink_factor = 1.247330950103979;
typedef typename std::iterator_traits<ForwardIterator>::difference_type difference_type;
difference_type gap = std::distance(first, last);
bool swaps = true;
while ( (gap > 1) || (swaps == true) ){
if (gap > 1)
gap = static_cast<difference_type>(gap/shrink_factor);
swaps = false;
ForwardIterator itLeft(first);
ForwardIterator itRight(first); std::advance(itRight, gap);
for ( ; itRight!=last; ++itLeft, ++itRight ){
if ( (*itRight) < (*itLeft) ){
std::iter_swap(itLeft, itRight);
swaps = true;
}
}
}
}</lang>
COBOL
This excerpt contains just enough of the procedure division to show the workings. See the example for the bubble sort for a more complete program. <lang COBOL> C-PROCESS SECTION.
C-000.
DISPLAY "SORT STARTING".
MOVE WC-SIZE TO WC-GAP.
PERFORM E-COMB UNTIL WC-GAP = 1 AND FINISHED.
DISPLAY "SORT FINISHED".
C-999.
EXIT.
E-COMB SECTION.
E-000.
IF WC-GAP > 1
DIVIDE WC-GAP BY 1.3 GIVING WC-GAP
IF WC-GAP = 9 OR 10
MOVE 11 TO WC-GAP.
MOVE 1 TO WC-SUB-1.
MOVE "Y" TO WF-FINISHED.
PERFORM F-SCAN UNTIL WC-SUB-1 + WC-GAP > WC-SIZE.
E-999.
EXIT.
F-SCAN SECTION.
F-000.
ADD WC-SUB-1 WC-GAP GIVING WC-SUB-2.
IF WB-ENTRY(WC-SUB-1) > WB-ENTRY(WC-SUB-2)
MOVE WB-ENTRY(WC-SUB-1) TO WC-TEMP
MOVE WB-ENTRY(WC-SUB-2) TO WB-ENTRY(WC-SUB-1)
MOVE WC-TEMP TO WB-ENTRY(WC-SUB-2)
MOVE "N" TO WF-FINISHED.
ADD 1 TO WC-SUB-1.
F-999.
EXIT.</lang>
Common Lisp
<lang lisp>(defparameter *shrink* 1.3)
(defun comb-sort (input)
(loop with input-size = (length input)
with gap = input-size
with swapped
do (when (> gap 1)
(setf gap (floor gap *shrink*)))
(setf swapped nil)
(loop for lo from 0
for hi from gap below input-size
when (> (aref input lo) (aref input hi))
do (rotatef (aref input lo) (aref input hi))
(setf swapped t))
while (or (> gap 1) swapped)
finally (return input)))</lang>
D
<lang d>import std.stdio, std.algorithm;
void combSort(T)(T[] input) pure nothrow @safe @nogc {
int gap = input.length; bool swaps = true;
while (gap > 1 || swaps) {
gap = max(1, cast(int)(gap / 1.2473));
swaps = false;
foreach (immutable i; 0 .. input.length - gap)
if (input[i] > input[i + gap]) {
input[i].swap(input[i + gap]);
swaps = true;
}
}
}
void main() {
auto data = [28, 44, 46, 24, 19, 2, 17, 11, 25, 4]; data.combSort; data.writeln;
}</lang>
- Output:
[2, 4, 11, 17, 19, 24, 25, 28, 44, 46]
Delphi
Adaptation of Pascal <lang Delphi> program Comb_sort;
{$APPTYPE CONSOLE}
uses
System.SysUtils, System.Types;
type
THelperIntegerDynArray = record helper for TIntegerDynArray public procedure CombSort; procedure FillRange(Count: integer); procedure Shuffle; function ToString: string; end;
{ THelperIntegerDynArray } procedure THelperIntegerDynArray.CombSort; var
i, gap, temp: integer; swapped: boolean;
begin
gap := length(self);
swapped := true;
while (gap > 1) or swapped do
begin
gap := trunc(gap / 1.3);
if (gap < 1) then
gap := 1;
swapped := false;
for i := 0 to length(self) - gap - 1 do
if self[i] > self[i + gap] then
begin
temp := self[i];
self[i] := self[i + gap];
self[i + gap] := temp;
swapped := true;
end;
end;
end;
procedure THelperIntegerDynArray.FillRange(Count: integer); var
i: Integer;
begin
SetLength(self, Count); for i := 0 to Count - 1 do Self[i] := i;
end;
procedure THelperIntegerDynArray.Shuffle; var
i, j, tmp: integer; count: integer;
begin
Randomize; count := Length(self); for i := 0 to count - 1 do begin j := i + Random(count - i); tmp := self[i]; self[i] := self[j]; self[j] := tmp; end;
end;
function THelperIntegerDynArray.ToString: string; var
value: Integer;
begin
Result := ;
for value in self do
begin
Result := Result + ' ' + Format('%4d', [value]);
end;
Result := '[' + Result.Trim + ']';
end;
var
data: TIntegerDynArray;
begin
data.FillRange(10);
data.Shuffle;
writeln('The data before sorting:');
Writeln(data.ToString, #10);
data.CombSort;
writeln('The data after sorting:');
Writeln(data.ToString, #10);
Readln;
end.</lang>
- Output:
The data before sorting: [1 9 0 6 2 7 3 5 4 8] The data after sorting: [0 1 2 3 4 5 6 7 8 9]
Eiffel
<lang Eiffel>
class COMB_SORT [G -> COMPARABLE]
feature
combsort (ar: ARRAY [G]): ARRAY [G] -- Sorted array in ascending order. require array_not_void: ar /= Void local gap, i: INTEGER swap: G swapped: BOOLEAN shrink: REAL_64 do create Result.make_empty Result.deep_copy (ar) gap := Result.count from until gap = 1 and swapped = False loop from i := Result.lower swapped := False until i + gap > Result.count loop if Result [i] > Result [i + gap] then swap := Result [i] Result [i] := Result [i + gap] Result [i + gap] := swap swapped := True end i := i + 1 end shrink := gap / 1.3 gap := shrink.floor if gap < 1 then gap := 1 end end ensure Result_is_set: Result /= Void Result_is_sorted: is_sorted (Result) end
feature {NONE}
is_sorted (ar: ARRAY [G]): BOOLEAN --- Is 'ar' sorted in ascending order? require ar_not_empty: ar.is_empty = False local i: INTEGER do Result := True from i := ar.lower until i = ar.upper loop if ar [i] > ar [i + 1] then Result := False end i := i + 1 end end
end
</lang> Test: <lang Eiffel> class APPLICATION
create make
feature
make do test := <<1, 5, 99, 2, 95, 7, -7>> io.put_string ("unsorted" + "%N") across test as ar loop io.put_string (ar.item.out + "%T") end io.put_string ("%N" + "sorted:" + "%N") create combsort test := combsort.combsort (test) across test as ar loop io.put_string (ar.item.out + "%T") end end
combsort: COMB_SORT [INTEGER]
test: ARRAY [INTEGER]
end </lang>
- Output:
unsorted: 1 5 99 2 95 7 -7 sorted: -7 1 2 5 7 95 99
Elena
ELENA 5.0 : <lang elena>import extensions; import system'math; import system'routines;
extension op {
combSort()
{
var list := self.clone();
real gap := list.Length;
bool swaps := true;
while (gap > 1 || swaps)
{
gap /= 1.247330950103979r;
if (gap<1) { gap := 1 };
int i := 0;
swaps := false;
while (i + gap.RoundedInt < list.Length)
{
int igap := i + gap.RoundedInt;
if (list[i] > list[igap])
{
list.exchange(i,igap);
swaps := true
};
i += 1
}
};
^ list
}
}
public program() {
var list := new int[]{3, 5, 1, 9, 7, 6, 8, 2, 4 };
console.printLine("before:", list.asEnumerable());
console.printLine("after :", list.combSort().asEnumerable())
}</lang>
- Output:
before:3,5,1,9,7,6,8,2,4 after :1,2,3,4,5,6,7,8,9
Elixir
<lang elixir>defmodule Sort do
def comb_sort([]), do: []
def comb_sort(input) do
comb_sort(List.to_tuple(input), length(input), 0) |> Tuple.to_list
end
defp comb_sort(output, 1, 0), do: output
defp comb_sort(input, gap, _) do
gap = max(trunc(gap / 1.25), 1)
{output,swaps} = Enum.reduce(0..tuple_size(input)-gap-1, {input,0}, fn i,{acc,swap} ->
if (x = elem(acc,i)) > (y = elem(acc,i+gap)) do
{acc |> put_elem(i,y) |> put_elem(i+gap,x), 1}
else
{acc,swap}
end
end)
comb_sort(output, gap, swaps)
end
end
(for _ <- 1..20, do: :rand.uniform(20)) |> IO.inspect |> Sort.comb_sort |> IO.inspect</lang>
- Output:
[10, 7, 8, 13, 4, 11, 13, 12, 18, 11, 5, 7, 3, 4, 15, 1, 17, 16, 7, 14] [1, 3, 4, 4, 5, 7, 7, 7, 8, 10, 11, 11, 12, 13, 13, 14, 15, 16, 17, 18]
Forth
This is an implementation of Comb sort with a different ending. Here Gnome sort is used, since it is rather small. The dataset is rather large, because otherwise the Comb sort routine would never kick in, passing control to Gnome sort almost right away. Note Comb sort can be kept much simpler this way, because Combsort11 optimizations and swapped flags can be discarded. <lang forth>defer precedes defer exchange
- gnomesort ( a n)
swap >r 1 ( n c)
begin ( n c)
over over > ( n c f)
while ( n c)
dup if ( n c)
dup dup 1- over over r@ precedes
if r@ exchange 1- else drop drop 1+ then
else 1+ then ( n c)
repeat drop drop r> drop ( --)
- combsort ( a n --)
dup begin ( a n g)
10 13 */ tuck >r >r 0 ( a g 0)
begin ( a g 0)
over r@ < ( a g 0 f)
while ( a g 0)
rot >r over over r@ precedes ( g 0 f)
if over over r@ exchange then ( g 0)
r> rot 1+ rot 1+ ( a g 0)
repeat drop drop r> r> ( a n g)
dup 9 < ( a n g f)
until drop gnomesort ( --)
create example
8 93 69 52 50 79 33 52 19 77 , , , , , , , , , , 72 85 11 61 64 80 64 76 47 65 , , , , , , , , , , 13 47 23 40 87 45 2 48 22 69 , , , , , , , , , , 1 53 33 60 57 14 76 32 59 12 , , , , , , , , , , 74 38 39 22 87 28 37 93 71 88 , , , , , , , , , , 56 35 48 99 21 35 26 28 58 85 , , , , , , , , , , 27 16 54 88 82 18 45 64 45 87 , , , , , , , , , , 98 97 60 77 43 1 64 0 32 89 , , , , , , , , , , 77 90 68 83 9 76 10 10 95 12 , , , , , , , , , , 99 23 74 58 54 25 50 9 94 1 , , , , , , , , , ,
- noname >r cells r@ + @ swap cells r> + @ swap < ; is precedes
- noname >r cells r@ + swap cells r> + over @ over @ swap rot ! swap ! ; is exchange
- .array 100 0 do example i cells + ? loop cr ;
.array example 100 combsort .array</lang>
Less Clever Version
This version is an academic demonstration that aligns with the algorithm. As is, it is limited to use one static array and sorts in ascending order only. <lang forth>\ combsort for the Forth Newbie (GForth)
HEX \ gratuitous variables ( Add clarity but NOT re-entrant) VARIABLE GAP VARIABLE SORTED \ flag
DECIMAL 100 CONSTANT SIZE
\ allocate a small array of cells CREATE Q SIZE CELLS ALLOT
\ operator to index into the array
- ]Q ( n -- adr) CELLS Q + ;
\ fill array and see array
- INITDATA ( -- ) SIZE 0 DO SIZE I - I ]Q ! LOOP ;
- SEEDATA ( -- ) CR SIZE 0 DO I ]Q @ U. LOOP ;
\ compute a new gap using scaled division \ factored out for this example. Could be a macro or inline code.
- /1.3 ( n -- n' ) 10 13 */ ;
\ factored out for this example. Could be a macro or inline code.
- XCHG ( adr1 adr2 n1 n2-- ) SWAP ROT ! SWAP ! ;
- COMBSORT ( n -- )
DUP >R \ copy n to return stack
1+ GAP ! \ set GAP to n+1
BEGIN
GAP @ /1.3 GAP ! \ re-compute the gap
SORTED ON
R@ GAP @ - 0 \ n-gap is loop limit
DO
I GAP @ + ]Q I ]Q \ compute array addresses
OVER @ OVER @ \ fetch the data in each cell
2DUP < \ compare a copy of the data
IF
XCHG \ Exchange the data in the cells
SORTED OFF \ flag we are not sorted
ELSE
2DROP 2DROP \ remove address and data
THEN
LOOP
SORTED @ GAP @ 0= AND \ test for complete
UNTIL
R> DROP ; \ remove 'n' from return stack </lang>
Fortran
<lang fortran>program Combsort_Demo
implicit none integer, parameter :: num = 20 real :: array(num) call random_seed call random_number(array) write(*,*) "Unsorted array:-" write(*,*) array write(*,*) call combsort(array) write(*,*) "Sorted array:-" write(*,*) array
contains
subroutine combsort(a)
real, intent(in out) :: a(:)
real :: temp
integer :: i, gap
logical :: swapped = .true.
gap = size(a)
do while (gap > 1 .or. swapped)
gap = gap / 1.3
if (gap < 1) gap = 1
swapped = .false.
do i = 1, size(a)-gap
if (a(i) > a(i+gap)) then
temp = a(i)
a(i) = a(i+gap)
a(i+gap) = temp;
swapped = .true.
end if
end do
end do
end subroutine combsort
end program Combsort_Demo</lang>
FreeBASIC
<lang Freebasic>' version 21-10-2016 ' compile with: fbc -s console ' for boundary checks on array's compile with: fbc -s console -exx
Sub compsort(bs() As Long)
' sort from lower bound to the highter bound ' array's can have subscript range from -2147483648 to +2147483647 Dim As Long lb = LBound(bs) Dim As Long ub = UBound(bs) Dim As Long gap = ub - lb Dim As Long done, i
Do
gap = Int (gap / 1.3)
If gap < 1 Then gap = 1
done = 0
For i = lb To ub - gap
If bs(i) > bs(i + gap) Then
Swap bs(i), bs(i + gap)
done = 1
End If
Next
Loop Until ((gap = 1) And (done = 0))
End Sub
Sub comp11sort(bs() As Long)
' sort from lower bound to the higher bound ' array's can have subscript range from -2147483648 to +2147483647 Dim As Long lb = LBound(bs) Dim As Long ub = UBound(bs) Dim As Long gap = ub - lb Dim As Long done, i
Do
gap = Int(gap / 1.24733)
If gap = 9 Or gap = 10 Then
gap = 11
ElseIf gap < 1 Then
gap = 1
End If
done = 0
For i = lb To ub - gap
If bs(i) > bs(i + gap) Then
Swap bs(i), bs(i + gap)
done = 1
End If
Next
Loop Until ((gap = 1) And (done = 0))
End Sub
' ------=< MAIN >=------
Dim As Long i, array(-7 To 7)
Dim As Long a = LBound(array), b = UBound(array)
Randomize Timer For i = a To b : array(i) = i : Next For i = a To b ' little shuffle
Swap array(i), array(Int(Rnd * (b - a +1)) + a)
Next
Print "normal comb sort" Print "unsorted "; For i = a To b : Print Using "####"; array(i); : Next : Print compsort(array()) ' sort the array Print " sorted "; For i = a To b : Print Using "####"; array(i); : Next : Print
Print Print "comb11 sort" For i = a To b ' little shuffle
Swap array(i), array(Int(Rnd * (b - a +1)) + a)
Next Print "unsorted "; For i = a To b : Print Using "####"; array(i); : Next : Print comp11sort(array()) ' sort the array Print " sorted "; For i = a To b : Print Using "####"; array(i); : Next : Print
' empty keyboard buffer While Inkey <> "" : Wend Print : Print "hit any key to end program" Sleep End</lang>
- Output:
normal comb sort unsorted -6 5 -1 -3 -7 6 1 7 -4 3 4 -2 -5 0 2 sorted -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 comb11 sort unsorted 4 -7 -1 1 2 3 -3 7 0 -2 6 -5 5 -6 -4 sorted -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7
Gambas
Click this link to run this code <lang gambas>Public Sub Main() Dim siToSort As Short[] = [249, 28, 111, 36, 171, 98, 29, 448, 44, 147, 154, 46, 102, 183, 24,
120, 19, 123, 2, 17, 226, 11, 211, 25, 191, 205, 77]
Dim siStart As Short Dim siGap As Short = siToSort.Max Dim bSorting, bGap1 As Boolean
Print "To sort: -" ShowWorking(siToSort) Print
Repeat
bSorting = False siStart = 0 If siGap = 1 Then bGap1 = True
Repeat
If siToSort[siStart] > siToSort[siStart + siGap] Then
Swap siToSort[siStart], siToSort[siStart + siGap]
bSorting = True
End If
Inc siStart
Until siStart + siGap > siToSort.Max
If bSorting Then ShowWorking(siToSort) siGap /= 1.3 If siGap < 1 Then siGap = 1
Until bSorting = False And bGap1 = True
End '----------------------------------------- Public Sub ShowWorking(siToSort As Short[]) Dim siCount As Short
For siCount = 0 To siToSort.Max
Print Str(siToSort[siCount]); If siCount <> siToSort.Max Then Print ",";
Next
End</lang> Output:
To sort: - 249,28,111,36,171,98,29,448,44,147,154,46,102,183,24,120,19,123,2,17,226,11,211,25,191,205,77 77,28,111,36,171,98,29,448,44,147,154,46,102,183,24,120,19,123,2,17,226,11,211,25,191,205,249 77,11,111,25,171,98,29,448,44,147,154,46,102,183,24,120,19,123,2,17,226,28,211,36,191,205,249 77,11,111,2,17,98,28,211,36,147,154,46,102,183,24,120,19,123,25,171,226,29,448,44,191,205,249 46,11,111,2,17,19,28,25,36,147,29,77,44,183,24,120,98,123,211,171,226,154,448,102,191,205,249 36,11,29,2,17,19,24,25,46,123,111,77,44,154,28,102,98,147,211,171,226,183,448,120,191,205,249 24,11,29,2,17,19,36,25,28,102,98,77,44,154,46,123,111,120,191,171,226,183,448,147,211,205,249 17,11,29,2,24,19,36,25,28,102,46,77,44,120,98,123,111,154,191,147,211,183,249,171,226,205,448 2,11,19,17,24,28,36,25,29,44,46,77,102,111,98,123,120,154,183,147,171,191,205,211,226,249,448 2,11,19,17,24,25,29,28,36,44,46,77,98,111,102,123,120,147,171,154,183,191,205,211,226,249,448 2,11,17,19,24,25,28,29,36,44,46,77,98,102,111,120,123,147,154,171,183,191,205,211,226,249,448
Go
<lang go>package main
import "fmt"
func main() {
a := []int{170, 45, 75, -90, -802, 24, 2, 66}
fmt.Println("before:", a)
combSort(a)
fmt.Println("after: ", a)
}
func combSort(a []int) {
if len(a) < 2 {
return
}
for gap := len(a); ; {
if gap > 1 {
gap = gap * 4 / 5
}
swapped := false
for i := 0; ; {
if a[i] > a[i+gap] {
a[i], a[i+gap] = a[i+gap], a[i]
swapped = true
}
i++
if i+gap >= len(a) {
break
}
}
if gap == 1 && !swapped {
break
}
}
}</lang>
More generic version that sorts anything that implements sort.Interface:
<lang go>package main
import (
"sort" "fmt"
)
func main() {
a := []int{170, 45, 75, -90, -802, 24, 2, 66}
fmt.Println("before:", a)
combSort(sort.IntSlice(a))
fmt.Println("after: ", a)
}
func combSort(a sort.Interface) {
if a.Len() < 2 {
return
}
for gap := a.Len(); ; {
if gap > 1 {
gap = gap * 4 / 5
}
swapped := false
for i := 0; ; {
if a.Less(i+gap, i) {
a.Swap(i, i+gap)
swapped = true
}
i++
if i+gap >= a.Len() {
break
}
}
if gap == 1 && !swapped {
break
}
}
}</lang>
Groovy
Combsort solution: <lang groovy>def makeSwap = { a, i, j -> print "."; a[i] ^= a[j]; a[j] ^= a[i]; a[i] ^= a[j] }
def checkSwap = { a, i, j -> [(a[i] > a[j])].find { it }.each { makeSwap(a, i, j) } }
def combSort = { input ->
def swap = checkSwap.curry(input)
def size = input.size()
def gap = size
def swapped = true
while (gap != 1 || swapped) {
gap = (gap / 1.247330950103979) as int
gap = (gap < 1) ? 1 : gap
swapped = (0..<(size-gap)).any { swap(it, it + gap) }
}
input
}</lang>
Combsort11 solution: <lang groovy>def combSort11 = { input ->
def swap = checkSwap.curry(input)
def size = input.size()
def gap = size
def swapped = true
while (gap != 1 || swapped) {
gap = (gap / 1.247330950103979) as int
gap = ((gap < 1) ? 1 : ([10,9].contains(gap) ? 11 : gap))
swapped = (0..<(size-gap)).any { swap(it, it + gap) }
}
input
}</lang>
Test: <lang groovy>println (combSort([23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78,4])) println (combSort11([23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78,4])) println () println (combSort([88,18,31,44,4,0,8,81,14,78,20,76,84,33,73,75,82,5,62,70,12,7,1])) println (combSort11([88,18,31,44,4,0,8,81,14,78,20,76,84,33,73,75,82,5,62,70,12,7,1]))</lang>
Output:
..................................................................................................................[4, 12, 14, 23, 24, 24, 31, 35, 38, 46, 51, 57, 57, 58, 76, 78, 89, 92, 95, 97, 99] ..........................................................................................................................[4, 12, 14, 23, 24, 24, 31, 35, 38, 46, 51, 57, 57, 58, 76, 78, 89, 92, 95, 97, 99] ...............................................................................................[0, 1, 4, 5, 7, 8, 12, 14, 18, 20, 31, 33, 44, 62, 70, 73, 75, 76, 78, 81, 82, 84, 88] ...............................................................................................[0, 1, 4, 5, 7, 8, 12, 14, 18, 20, 31, 33, 44, 62, 70, 73, 75, 76, 78, 81, 82, 84, 88]
Haskell
<lang haskell>import Data.List import Control.Arrow import Control.Monad
flgInsert x xs = ((x:xs==) &&& id)$ insert x xs
gapSwapping k = (and *** concat. transpose). unzip
. map (foldr (\x (b,xs) -> first (b &&)$ flgInsert x xs) (True,[])) . transpose. takeWhile (not.null). unfoldr (Just. splitAt k)
combSort xs = (snd. fst) $ until (\((b,_),g)-> b && g==1)
(\((_,xs),g) ->(gapSwapping g xs, fg g)) ((False,xs), fg $ length xs) where fg = max 1. truncate. (/1.25). fromIntegral</lang>
Example: <lang haskell>*Main> combSort [23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78] [12,14,23,24,24,31,35,38,46,51,57,57,58,76,78,89,92,95,97,99]</lang>
Haxe
<lang haxe>class CombSort {
@:generic
public static function sort<T>(arr:Array<T>) {
var gap:Float = arr.length;
var swaps = true;
while (gap > 1 || swaps) {
gap /= 1.247330950103979;
if (gap < 1) gap = 1.0;
var i = 0;
swaps = false;
while (i + gap < arr.length) {
var igap = i + Std.int(gap);
if (Reflect.compare(arr[i], arr[igap]) > 0) {
var temp = arr[i];
arr[i] = arr[igap];
arr[igap] = temp;
swaps = true;
}
i++;
}
}
}
}
class Main {
static function main() {
var integerArray = [1, 10, 2, 5, -1, 5, -19, 4, 23, 0];
var floatArray = [1.0, -3.2, 5.2, 10.8, -5.7, 7.3,
3.5, 0.0, -4.1, -9.5];
var stringArray = ['We', 'hold', 'these', 'truths', 'to',
'be', 'self-evident', 'that', 'all',
'men', 'are', 'created', 'equal'];
Sys.println('Unsorted Integers: ' + integerArray);
CombSort.sort(integerArray);
Sys.println('Sorted Integers: ' + integerArray);
Sys.println('Unsorted Floats: ' + floatArray);
CombSort.sort(floatArray);
Sys.println('Sorted Floats: ' + floatArray);
Sys.println('Unsorted Strings: ' + stringArray);
CombSort.sort(stringArray);
Sys.println('Sorted Strings: ' + stringArray);
}
}</lang>
- Output:
Unsorted Integers: [1,10,2,5,-1,5,-19,4,23,0] Sorted Integers: [-19,-1,0,1,2,4,5,5,10,23] Unsorted Floats: [1,-3.2,5.2,10.8,-5.7,7.3,3.5,0,-4.1,-9.5] Sorted Floats: [-9.5,-5.7,-4.1,-3.2,0,1,3.5,5.2,7.3,10.8] Unsorted Strings: [We,hold,these,truths,to,be,self-evident,that,all,men,are,created,equal] Sorted Strings: [We,all,are,be,created,equal,hold,men,self-evident,that,these,to,truths]
Icon and Unicon
<lang Icon>procedure main() #: demonstrate various ways to sort a list and string
demosort(combsort,[3, 14, 1, 5, 9, 2, 6, 3],"qwerty")
end
procedure combsort(X,op) #: return sorted X local gap,swapped,i
op := sortop(op,X) # select how and what we sort
swappped := gap := *X # initialize gap size and say swapped
until /swapped & gap = 1 do {
gap := integer(gap / 1.25) # update the gap value for a next comb
gap <:= 1 # minimum gap of 1
swapped := &null
i := 0
until (i +:= 1) + gap > *X do # a single "comb" over the input list
if op(X[i+gap],X[i]) then
X[i+1] :=: X[swapped := i] # swap and flag as unsorted
}
return X
end</lang>
Note: This example relies on the supporting procedures 'sortop', and 'demosort' in Bubble Sort. The full demosort exercises the named sort of a list with op = "numeric", "string", ">>" (lexically gt, descending),">" (numerically gt, descending), a custom comparator, and also a string.
Abbreviated sample output:
Sorting Demo using procedure combsort
on list : [ 3 14 1 5 9 2 6 3 ]
with op = &null: [ 1 2 3 3 5 6 9 14 ] (0 ms)
...
on string : "qwerty"
with op = &null: "eqrtwy" (0 ms)
Io
<lang io>List do(
combSortInPlace := method(
gap := size
swap := true
while(gap > 1 or swap,
swap = false
gap = (gap / 1.25) floor
for(i, 0, size - gap,
if(at(i) > at(i + gap),
swap = true
swapIndices(i, i + gap)
)
)
)
self)
)
lst := list(23, 76, 99, 58, 97, 57, 35, 89, 51, 38, 95, 92, 24, 46, 31, 24, 14, 12, 57, 78) lst combSortInPlace println # ==> list(12, 14, 23, 24, 24, 31, 35, 38, 46, 51, 57, 57, 58, 76, 78, 89, 92, 95, 97, 99)</lang>
IS-BASIC
<lang IS-BASIC>100 PROGRAM "CombSrt.bas" 110 RANDOMIZE 120 NUMERIC ARRAY(11 TO 30) 130 CALL INIT(ARRAY) 140 CALL WRITE(ARRAY) 150 CALL COMBSORT(ARRAY) 160 CALL WRITE(ARRAY) 170 DEF INIT(REF A) 180 FOR I=LBOUND(A) TO UBOUND(A) 190 LET A(I)=RND(98)+1 200 NEXT 210 END DEF 220 DEF WRITE(REF A) 230 FOR I=LBOUND(A) TO UBOUND(A) 240 PRINT A(I); 250 NEXT 260 PRINT 270 END DEF 280 DEF COMBSORT(REF A) 290 LET N,GAP=UBOUND(A):LET SW=1 300 DO WHILE GAP>1 OR SW 310 LET GAP=MAX(INT(GAP/1.3),1):LET SW=0 320 FOR I=LBOUND(A) TO N-GAP 330 IF A(I)>A(I+GAP) THEN 340 LET T=A(I):LET A(I)=A(I+GAP):LET A(I+GAP)=T 350 LET SW=1 360 END IF 370 NEXT 380 LOOP 390 END DEF</lang>
J
Large gap sizes allow some parallelism in comparisons and swaps. (If the gap size is G, then G pairs can be compared and swapped in parallel.) Beyond that, however, the data flow complexity of this algorithm requires a fair bit of micro-management.
<lang J>combSort=:3 :0
gap=. #y
whilst.1 < gap+swaps do.
swaps=. 0
i=. i.2,gap=. 1 >. <.gap%1.25
while.{:$i=.i #"1~ ({: i) < #y do.
swaps=.swaps+#{:k=.i #"1~b=. >/ i{y
i=. i+gap
y=.((|.k){y) k} y
end.
end.
y
)</lang>
Example use:
combSort 23 76 99 58 97 57 35 89 51 38 95 92 24 46 31 24 14 12 57 78 12 14 23 24 24 31 35 38 46 51 57 57 58 76 78 89 92 95 97 99 combSort 88 18 31 44 4 0 8 81 14 78 20 76 84 33 73 75 82 5 62 70 0 4 5 8 14 18 20 31 33 44 62 70 73 75 76 78 81 82 84 88
Java
This is copied from the Wikipedia article. <lang java>public static <E extends Comparable<? super E>> void sort(E[] input) {
int gap = input.length;
boolean swapped = true;
while (gap > 1 || swapped) {
if (gap > 1) {
gap = (int) (gap / 1.3);
}
swapped = false;
for (int i = 0; i + gap < input.length; i++) {
if (input[i].compareTo(input[i + gap]) > 0) {
E t = input[i];
input[i] = input[i + gap];
input[i + gap] = t;
swapped = true;
}
}
}
}</lang>
JavaScript
<lang javascript>
// Node 5.4.1 tested implementation (ES6)
function is_array_sorted(arr) {
var sorted = true;
for (var i = 0; i < arr.length - 1; i++) {
if (arr[i] > arr[i + 1]) {
sorted = false;
break;
}
}
return sorted;
}
// Array to sort var arr = [4, 9, 0, 3, 1, 5];
var iteration_count = 0; var gap = arr.length - 2; var decrease_factor = 1.25;
// Until array is not sorted, repeat iterations
while (!is_array_sorted(arr)) {
// If not first gap
if (iteration_count > 0)
// Calculate gap
gap = (gap == 1) ? gap : Math.floor(gap / decrease_factor);
// Set front and back elements and increment to a gap
var front = 0;
var back = gap;
while (back <= arr.length - 1) {
// If elements are not ordered swap them
if (arr[front] > arr[back]) {
var temp = arr[front];
arr[front] = arr[back];
arr[back] = temp;
}
// Increment and re-run swapping
front += 1;
back += 1;
}
iteration_count += 1;
}
// Print the sorted array console.log(arr);
}</lang>
- Output:
[0, 1, 3, 4, 5, 9]
jq
An implementation of the pseudo-code in the task description: <lang jq># Input should be the array to be sorted. def combsort:
# As soon as "condition" is true, emit . and stop: def do_until(condition; next): def u: if condition then . else (next|u) end; u;
def swap(i;j): if i==j then . else .[i] as $tmp | .[i] = .[j] | .[j] = $tmp end;
. as $in
| length as $length
# state: [gap, swaps, array] where:
# gap is the gap size;
# swaps is a boolean flag indicating a swap has occurred,
# implying that the array might not be sorted;
# array is the current state of the array being sorted
| [ $length, false, $in ]
| do_until( .[0] == 1 and .[1] == false;
# update the gap value for the next "comb":
([1, ((.[0] / 1.25) | floor)] | max) as $gap # minimum gap is 1
# state: [i, swaps, array]
| [0, false, .[2]]
# a single "comb" over the input list:
| do_until( (.[0] + $gap) >= $length;
.[0] as $i
| if .[2][$i] > .[2][$i+$gap] then
[$i+1, true, (.[2]|swap($i; $i+$gap))]
else .[0] += 1
end)
| .[0] = $gap )
| .[2] ;</lang>
Julia
<lang julia># v0.6
function combsort!(x::Array)::Array
gap, swaps = length(x), true
while gap > 1 || swaps
gap = floor(Int, gap / 1.25)
i, swaps = 0, false
while i + gap < length(x)
if x[i+1] > x[i+1+gap]
x[i+1], x[i+1+gap] = x[i+1+gap], x[i+1]
swaps = true
end
i += 1
end
end
return x
end
x = randn(100) @show x combsort!(x) @assert issorted(x)</lang>
- Output:
x = [1.41167, 1.19626, 0.821703, 0.336024, -0.708447, 0.694578, 1.49075, -1.07124, -1.59686, -0.720135] combsort!(x) = [-1.59686, -1.07124, -0.720135, -0.708447, 0.336024, 0.694578, 0.821703, 1.19626, 1.41167, 1.49075]
Kotlin
<lang scala>// version 1.1.2
fun <T : Comparable<T>> combSort(input: Array<T>) {
var gap = input.size
if (gap <= 1) return // already sorted
var swaps = false
while (gap > 1 || swaps) {
gap = (gap / 1.247331).toInt()
if (gap < 1) gap = 1
var i = 0
swaps = false
while (i + gap < input.size) {
if (input[i] > input[i + gap]) {
val tmp = input[i]
input[i] = input[i + gap]
input[i + gap] = tmp
swaps = true
}
i++
}
}
}
fun main(args: Array<String>) {
val ia = arrayOf(28, 44, 46, 24, 19, 2, 17, 11, 25, 4)
println("Unsorted : ${ia.contentToString()}")
combSort(ia)
println("Sorted : ${ia.contentToString()}")
println()
val ca = arrayOf('X', 'B', 'E', 'A', 'Z', 'M', 'S', 'L', 'Y', 'C')
println("Unsorted : ${ca.contentToString()}")
combSort(ca)
println("Sorted : ${ca.contentToString()}")
}</lang>
- Output:
Unsorted : [28, 44, 46, 24, 19, 2, 17, 11, 25, 4] Sorted : [2, 4, 11, 17, 19, 24, 25, 28, 44, 46] Unsorted : [X, B, E, A, Z, M, S, L, Y, C] Sorted : [A, B, C, E, L, M, S, X, Y, Z]
Liberty BASIC
<lang lb> 'randomize 0.5 itemCount = 20
dim item(itemCount)
for i = 1 to itemCount
item(i) = int(rnd(1) * 100)
next i
print "Before Sort"
for i = 1 to itemCount
print item(i)
next i
print: print
't0=time$("ms")
gap=itemCount
while gap>1 or swaps <> 0
gap=int(gap/1.25)
'if gap = 10 or gap = 9 then gap = 11 'uncomment to get Combsort11
if gap <1 then gap = 1
i = 1
swaps = 0
for i = 1 to itemCount-gap
if item(i) > item(i + gap) then
temp = item(i)
item(i) = item(i + gap)
item(i + gap) = temp
swaps = 1
end if
next
wend
print "After Sort"
't1=time$("ms") 'print t1-t0
for i = 1 to itemCount
print item(i)
next i
end </lang>
Lua
<lang lua>function combsort(t)
local gapd, gap, swaps = 1.2473, #t, 0
while gap + swaps > 1 do
local k = 0
swaps = 0
if gap > 1 then gap = math.floor(gap / gapd) end
for k = 1, #t - gap do
if t[k] > t[k + gap] then
t[k], t[k + gap], swaps = t[k + gap], t[k], swaps + 1
end
end
end
return t
end
print(unpack(combsort{3,5,1,2,7,4,8,3,6,4,1}))</lang>
Maple
<lang Maple>swap := proc(arr, a, b) local temp; temp := arr[a]: arr[a] := arr[b]: arr[b] := temp: end proc: newGap := proc(gap) local new; new := trunc(gap*10/13); if (new < 1) then return 1; end if; return new; end proc; combsort := proc(arr, len) local gap, swapped,i, temp; swapped := true: gap := len: while ((not gap = 1) or swapped) do gap := newGap(gap): swapped := false: for i from 1 to len-gap by 1 do if (arr[i] > arr[i+gap]) then temp := arr[i]: arr[i] := arr[i+gap]: arr[i+gap] := temp: swapped:= true: end if: end do: end do: end proc: arr := Array([17,3,72,0,36,2,3,8,40,0]); combsort(arr, numelems(arr)); arr;</lang>
- Output:
[0,0,2,3,3,8,17,36,40,72]
Mathematica/Wolfram Language
<lang Mathematica>combSort[list_] := Module[{ gap = 0, listSize = 0, swaps = True},
gap = listSize = Length[list];
While[ !((gap <= 1) && (swaps == False)),
gap = Floor@Divide[gap, 1.25];
If[ gap < 1, gap = 1]; i = 1; swaps = False;
While[ ! ((i + gap - 1) >= listSize),
If[ listi > listi + gap, swaps = True;
listi ;; i + gap = listi + gap ;; i ;; -1;
];
i++;
]
]
]</lang>
combSort@{2, 1, 3, 7, 6}
->{1, 2, 3, 6, 7}
MATLAB / Octave
<lang MATLAB>function list = combSort(list)
listSize = numel(list);
gap = int32(listSize); %Coerce gap to an int so we can use the idivide function
swaps = true; %Swap flag
while not((gap <= 1) && (swaps == false))
gap = idivide(gap,1.25,'floor'); %Int divide, floor the resulting operation
if gap < 1
gap = 1;
end
i = 1; %i equals 1 because all arrays are 1 based in MATLAB
swaps = false;
%i + gap must be subtracted by 1 because the pseudo-code was writen
%for 0 based arrays
while not((i + gap - 1) >= listSize)
if (list(i) > list(i+gap))
list([i i+gap]) = list([i+gap i]); %swap
swaps = true;
end
i = i + 1;
end %while
end %while
end %combSort</lang>
Sample Output: <lang MATLAB>>> combSort([4 3 1 5 6 2])
ans =
1 2 3 4 5 6</lang>
MAXScript
<lang MAXScript>fn combSort arr = ( local gap = arr.count local swaps = 1 while not (gap == 1 and swaps == 0) do ( gap = (gap / 1.25) as integer if gap < 1 do ( gap = 1 ) local i = 1 swaps = 0 while not (i + gap > arr.count) do ( if arr[i] > arr[i+gap] do ( swap arr[i] arr[i+gap] swaps = 1 ) i += 1
)
)
return arr
)</lang>
Output:
<lang MAXScript>
a = for i in 1 to 10 collect random 1 10
- (2, 6, 5, 9, 10, 7, 2, 6, 1, 4)
combsort a
- (1, 2, 2, 4, 5, 6, 6, 7, 9, 10)
</lang>
NetRexx
<lang NetRexx>/* NetRexx */
options replace format comments java crossref savelog symbols binary
placesList = [String -
"UK London", "US New York" - , "US Boston", "US Washington" - , "UK Washington", "US Birmingham" - , "UK Birmingham", "UK Boston" -
] sortedList = combSort(String[] Arrays.copyOf(placesList, placesList.length))
lists = [placesList, sortedList] loop ln = 0 to lists.length - 1
cl = lists[ln] loop ct = 0 to cl.length - 1 say cl[ct] end ct say end ln
return
method combSort(input = String[]) public constant binary returns String[]
swaps = isTrue
gap = input.length
loop label comb until gap = 1 & \swaps
gap = int gap / 1.25
if gap < 1 then
gap = 1
i_ = 0
swaps = isFalse
loop label swaps until i_ + gap >= input.length
if input[i_].compareTo(input[i_ + gap]) > 0 then do
swap = input[i_]
input[i_] = input[i_ + gap]
input[i_ + gap] = swap
swaps = isTrue
end
i_ = i_ + 1
end swaps
end comb
return input
method isTrue public constant binary returns boolean
return 1 == 1
method isFalse public constant binary returns boolean
return \isTrue
</lang>
- Output
UK London US New York US Boston US Washington UK Washington US Birmingham UK Birmingham UK Boston UK Birmingham UK Boston UK London UK Washington US Birmingham US Boston US New York US Washington
Nim
<lang nim>proc combSort[T](a: var openarray[T]) =
var gap = a.len
var swapped = true
while gap > 1 or swapped:
gap = gap * 10 div 13
if gap == 9 or gap == 10: gap = 11
if gap < 1: gap = 1
swapped = false
var i = 0
for j in gap ..< a.len:
if a[i] > a[j]:
swap a[i], a[j]
swapped = true
inc i
var a = @[4, 65, 2, -31, 0, 99, 2, 83, 782] combSort a echo a</lang> Output:
@[-31, 0, 2, 2, 4, 65, 83, 99, 782]
Objeck
<lang objeck> bundle Default {
class Stooge {
function : Main(args : String[]) ~ Nil {
nums := [3, 5, 1, 9, 7, 6, 8, 2, 4];
CombSort(nums);
each(i : nums) {
IO.Console->Print(nums[i])->Print(",");
};
IO.Console->PrintLine();
}
function : CombSort(input : Int[]) ~ Nil {
gap : Float := input->Size();
swaps := true;
while(gap > 1 | swaps) {
gap /= 1.247330950103979;
if(gap < 1) { gap := 1; };
i : Int := 0;
swaps := false;
while(i + gap < input->Size()) {
igap : Int := i + gap->As(Int);
if (input[i] > input[igap]) {
swap : Int := input[i];
input[i] := input[igap];
input[igap] := swap;
swaps := true;
};
i += 1;
};
};
}
}
} </lang>
OCaml
<lang ocaml>let comb_sort ~input =
let input_length = Array.length input in
let gap = ref(input_length) in
let swapped = ref true in
while (!gap > 1 || !swapped) do
if (!gap > 1) then
gap := int_of_float (float !gap /. 1.3);
swapped := false;
for i = 0 to input_length - !gap do
if input.(i) > input.(i + !gap) then begin
let tmp = input.(i) in
input.(i) <- input.(i + !gap);
input.(i + !gap) <- tmp;
swapped := true;
end
done
done
- </lang>
Oz
<lang oz>declare
proc {CombSort Arr}
Low = {Array.low Arr}
High = {Array.high Arr}
Size = High - Low + 1
Gap = {NewCell Size}
Swapped = {NewCell true}
proc {Swap I J}
Arr.J := (Arr.I := Arr.J)
end
in
for while:@Gap>1 orelse @Swapped do
if @Gap > 1 then
Gap := {Float.toInt {Floor {Int.toFloat @Gap} / 1.3}}
end
Swapped := false
for I in Low..High-@Gap do
if Arr.I > Arr.(I+@Gap) then
{Swap I I+@Gap}
Swapped := true
end
end
end
end
Arr = {Tuple.toArray unit(3 1 4 1 5 9 2 6 5)}
in
{CombSort Arr}
{Show {Array.toRecord unit Arr}}</lang>
PARI/GP
<lang parigp>combSort(v)={
my(phi=(1+sqrt(5))/2,magic=1/(1-exp(-phi)),g=#v,swaps);
while(g>1 | swaps,
if(g>1, g\=magic);
swaps=0;
for(i=1,#v-g,
if(v[i]>v[i+g],
my(t=v[i]);
v[i]=v[i+g];
v[i+g]=t;
swaps++
)
)
);
v
};</lang>
Pascal
<lang pascal>program CombSortDemo;
// NOTE: The array is 1-based
// If you want to use this code on a 0-based array, see below
type
TIntArray = array[1..40] of integer;
var
data: TIntArray; i: integer;
procedure combSort(var a: TIntArray);
var
i, gap, temp: integer;
swapped: boolean;
begin
gap := length(a);
swapped := true;
while (gap > 1) or swapped do
begin
gap := trunc(gap / 1.3);
if (gap < 1) then
gap := 1;
swapped := false;
for i := 1 to length(a) - gap do
if a[i] > a[i+gap] then
begin
temp := a[i];
a[i] := a[i+gap];
a[i+gap] := temp;
swapped := true;
end;
end;
end;
begin
Randomize;
writeln('The data before sorting:');
for i := low(data) to high(data) do
begin
data[i] := Random(high(data));
write(data[i]:4);
end;
writeln;
combSort(data);
writeln('The data after sorting:');
for i := low(data) to high(data) do
begin
write(data[i]:4);
end;
writeln;
end.</lang> Output:
The data before sorting: 10 26 32 10 9 32 38 37 12 9 16 7 25 1 37 7 24 22 7 36 2 5 10 5 33 35 32 18 5 28 7 5 36 12 16 36 24 3 29 15 The data after sorting: 1 2 3 5 5 5 5 7 7 7 7 9 9 10 10 10 12 12 15 16 16 18 22 24 24 25 26 28 29 32 32 32 33 35 36 36 36 37 37 38
<lang pascal>program CombSortDemo;
// NOTE: The array is 0-based
// If you want to use this code on a 1-based array, see above
type
TIntArray = array[0..39] of integer;
var
data: TIntArray; i: integer;
procedure combSort(var a: TIntArray);
var
i, gap, temp: integer;
swapped: boolean;
begin
gap := length(a);
swapped := true;
while (gap > 1) or swapped do
begin
gap := trunc(gap / 1.3);
if (gap < 1) then
gap := 1;
swapped := false;
for i := 0 to length(a) - gap - 1 do
if a[i] > a[i+gap] then
begin
temp := a[i];
a[i] := a[i+gap];
a[i+gap] := temp;
swapped := true;
end;
end;
end;
begin
Randomize;
writeln('The data before sorting:');
for i := low(data) to high(data) do
begin
data[i] := Random(high(data));
write(data[i]:4);
end;
writeln;
combSort(data);
writeln('The data after sorting:');
for i := low(data) to high(data) do
begin
write(data[i]:4);
end;
writeln;
end.</lang>
Perl
<lang perl>sub combSort {
my @arr = @_;
my $gap = @arr;
my $swaps = 1;
while ($gap > 1 || $swaps) {
$gap /= 1.25 if $gap > 1;
$swaps = 0;
foreach my $i (0 .. $#arr - $gap) {
if ($arr[$i] > $arr[$i+$gap]) {
@arr[$i, $i+$gap] = @arr[$i+$gap, $i];
$swaps = 1;
}
}
}
return @arr;
}</lang>
Phix
with javascript_semantics function comb_sort(sequence s) integer gap = length(s)-1 while 1 do gap = max(floor(gap/1.3),1) integer swapped = 0 for i=1 to length(s)-gap do object si = s[i] if si>s[i+gap] then s[i] = s[i+gap] s[i+gap] = si swapped = 1 end if end for if gap=1 and swapped=0 then exit end if end while return s end function ?comb_sort(shuffle(tagset(10)))
- Output:
{1,2,3,4,5,6,7,8,9,10}
PHP
<lang php>function combSort($arr){ $gap = count($arr);
$swap = true;
while ($gap > 1 || $swap){ if($gap > 1) $gap /= 1.25;
$swap = false; $i = 0; while($i+$gap < count($arr)){ if($arr[$i] > $arr[$i+$gap]){ list($arr[$i], $arr[$i+$gap]) = array($arr[$i+$gap],$arr[$i]); $swap = true; } $i++; } } return $arr; }</lang>
PicoLisp
<lang PicoLisp>(de combSort (Lst)
(let (Gap (length Lst) Swaps NIL)
(while (or (> Gap 1) Swaps)
(setq Gap (max 1 (/ (* Gap 4) 5)))
(off Swaps)
(use Lst
(for (G (cdr (nth Lst Gap)) G (cdr G))
(when (> (car Lst) (car G))
(xchg Lst G)
(on Swaps) )
(pop 'Lst) ) ) ) )
Lst )</lang>
Output:
: (combSort (88 18 31 44 4 0 8 81 14 78 20 76 84 33 73 75 82 5 62 70)) -> (0 4 5 8 14 18 20 31 33 44 62 70 73 75 76 78 81 82 84 88)
PL/I
<lang PL/I> /* From the pseudocode. */ comb_sort: procedure (A);
declare A(*) fixed; declare t fixed; declare (i, gap) fixed binary (31); declare swaps bit (1) aligned;
gap = hbound(A,1) - lbound(A,1); /* initialize the gap size. */
do until (gap <= 1 & swaps);
/* update the gap value for a next comb. */
put skip data (gap);
gap = gap / 1.25e0;
put skip data (gap);
swaps = '1'b;
/* a single "comb" over the array. */
do i = lbound(A,1) by 1 until (i + gap >= hbound(A,1));
if A(i) > A(i+gap) then
do;
t = A(i); A(i) = A(i+gap); A(i+gap) = t;
swaps = '0'b; /* Flag a swap has occurred, so */
/* the list is not guaranteed sorted. */
end;
end;
end;
end comb_sort; </lang>
PowerShell
Massaging gap to always hit 11. Based on PowerShell from Cocktail Sort <lang PowerShell>function CombSort ($a) {
$l = $a.Length
$gap = 11 while( $gap -lt $l ) { $gap = [Math]::Floor( $gap*1.3 ) } if( $l -gt 1 ) { $hasChanged = $true :outer while ($hasChanged -or ( $gap -gt 1 ) ) { $count = 0 $hasChanged = $false if( $gap -gt 1 ) { $gap = [Math]::Floor( $gap/1.3 ) } else { $l-- } for ($i = 0; $i -lt ( $l - $gap ); $i++) { if ($a[$i] -gt $a[$i+$gap]) { $a[$i], $a[$i+$gap] = $a[$i+$gap], $a[$i] $hasChanged = $true $count++ } } } } $a }
$l = 100; CombSort ( 1..$l | ForEach-Object { $Rand = New-Object Random }{ $Rand.Next( -( $l - 1 ), $l - 1 ) } )</lang>
PureBasic
Implementation of CombSort11. <lang PureBasic>;sorts an array of integers Procedure combSort11(Array a(1))
Protected i, gap, swaps = 1
Protected nElements = ArraySize(a())
gap = nElements
While (gap > 1) Or (swapped = 1)
gap * 10 / 13
If gap = 9 Or gap = 10: gap = 11: EndIf
If gap < 1: gap = 1: EndIf
i = 0
swaps = 0
While (i + gap) <= nElements
If a(i) > a(i + gap)
Swap a(i), a(i + gap)
swaps = 1
EndIf
i + 1
Wend
Wend
EndProcedure</lang> Implementation of CombSort. <lang PureBasic>;sorts an array of integers Procedure combSort(Array a(1))
Protected i, gap, swaps = 1
Protected nElements = ArraySize(a())
gap = nElements
While (gap > 1) Or (swaps = 1)
gap = Int(gap / 1.25)
i = 0
swaps = 0
While (i + gap) <= nElements
If a(i) > a(i + gap)
Swap a(i), a(i + gap)
swaps = 1
EndIf
i + 1
Wend
Wend
EndProcedure</lang>
Python
<lang python>>>> def combsort(input):
gap = len(input)
swaps = True
while gap > 1 or swaps:
gap = max(1, int(gap / 1.25)) # minimum gap is 1
swaps = False
for i in range(len(input) - gap):
j = i+gap
if input[i] > input[j]:
input[i], input[j] = input[j], input[i]
swaps = True
>>> y = [88, 18, 31, 44, 4, 0, 8, 81, 14, 78, 20, 76, 84, 33, 73, 75, 82, 5, 62, 70]
>>> combsort(y)
>>> assert y == sorted(y)
>>> y
[0, 4, 5, 8, 14, 18, 20, 31, 33, 44, 62, 70, 73, 75, 76, 78, 81, 82, 84, 88]
>>> </lang>
R
<lang R> comb.sort<-function(a){
gap<-length(a)
swaps<-1
while(gap>1 & swaps==1){
gap=floor(gap/1.3)
if(gap<1){
gap=1
}
swaps=0
i=1
while(i+gap<=length(a)){
if(a[i]>a[i+gap]){
a[c(i,i+gap)] <- a[c(i+gap,i)]
swaps=1
}
i<-i+1
}
}
return(a)
}
</lang>
Racket
<lang racket>
- lang racket
(require (only-in srfi/43 vector-swap!))
(define (comb-sort xs)
(define (ref i) (vector-ref xs i))
(define (swap i j) (vector-swap! xs i j))
(define (new gap) (max 1 (exact-floor (/ gap 1.25))))
(define size (vector-length xs))
(let loop ([gap size] [swaps 0])
(unless (and (= gap 1) (= swaps 0))
(loop (new gap)
(for/fold ([swaps 0]) ([i (in-range 0 (- size gap))])
(cond
[(> (ref i) (ref (+ i gap)))
(swap i (+ i gap))
(+ swaps 1)]
[swaps])))))
xs)
</lang>
Raku
(formerly Perl 6)
<lang perl6>sub comb_sort ( @a is copy ) {
my $gap = +@a;
my $swaps = 1;
while $gap > 1 or $swaps {
$gap = ( ($gap * 4) div 5 ) || 1 if $gap > 1;
$swaps = 0;
for ^(+@a - $gap) -> $i {
my $j = $i + $gap;
if @a[$i] > @a[$j] {
@a[$i, $j] .= reverse;
$swaps = 1;
}
}
}
return @a;
}
my @weights = (^50).map: { 100 + ( 1000.rand.Int / 10 ) }; say @weights.sort.Str eq @weights.&comb_sort.Str ?? 'ok' !! 'not ok'; </lang>
REXX
<lang rexx>/*REXX program sorts and displays a stemmed array using the comb sort algorithm. */ call gen /*generate the @ array elements. */ call show 'before sort' /*display the before array elements. */
say copies('▒', 60) /*display a separator line (a fence). */
call combSort # /*invoke the comb sort (with # entries)*/ call show ' after sort' /*display the after array elements. */ exit 0 /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ combSort: procedure expose @.; parse arg N /*N: is the number of @ elements. */
g= N-1 /*G: is the gap between the sort COMBs*/
do until g<=1 & done; done= 1 /*assume sort is done (so far). */
g= g * 0.8 % 1 /*equivalent to: g= trunc( g / 1.25) */
if g==0 then g= 1 /*handle case of the gap is too small. */
do j=1 until $>=N; $= j+g /*$: a temporary index (pointer). */
if @.j>@.$ then do; _= @.j; @.j= @.$; @.$= _; done= 0; end
end /*j*/
end /*until*/ /* [↑] swap two elements in the array.*/
return
/*──────────────────────────────────────────────────────────────────────────────────────*/ gen: @.=; @.1 = '----polygon--- sides' ; @.12 = "dodecagon 12"
@.2 = '============== =======' ; @.13 = "tridecagon 13"
@.3 = 'triangle 3' ; @.14 = "tetradecagon 14"
@.4 = 'quadrilateral 4' ; @.15 = "pentadecagon 15"
@.5 = 'pentagon 5' ; @.16 = "hexadecagon 16"
@.6 = 'hexagon 6' ; @.17 = "heptadecagon 17"
@.7 = 'heptagon 7' ; @.18 = "octadecagon 18"
@.8 = 'octagon 8' ; @.19 = "enneadecagon 19"
@.9 = 'nonagon 9' ; @.20 = "icosagon 20"
@.10 = 'decagon 10' ; @.21 = "hectogon 100"
@.11 = 'hendecagon 11' ; @.22 = "chiliagon 1000"
@.23 = "myriagon 10000"
do #=1 while @.#\==; end /*find how many elements in @ */
#= #-1; w= length(#); return /*adjust # because of DO loop.*/
/*──────────────────────────────────────────────────────────────────────────────────────*/ show: do k=1 for #; say right('element',15) right(k,w) arg(1)":" @.k; end; return</lang>
Data trivia: A hendecagon (also known as an undecagon or unidecagon) is from the Greek word hendeka [eleven] and gon─ [corner].
- output:
(Shown at three-quarter size.)
element 1 before sort: ----polygon--- sides
element 2 before sort: ============== =======
element 3 before sort: triangle 3
element 4 before sort: quadrilateral 4
element 5 before sort: pentagon 5
element 6 before sort: hexagon 6
element 7 before sort: heptagon 7
element 8 before sort: octagon 8
element 9 before sort: nonagon 9
element 10 before sort: decagon 10
element 11 before sort: hendecagon 11
element 12 before sort: dodecagon 12
element 13 before sort: tridecagon 13
element 14 before sort: tetradecagon 14
element 15 before sort: pentadecagon 15
element 16 before sort: hexadecagon 16
element 17 before sort: heptadecagon 17
element 18 before sort: octadecagon 18
element 19 before sort: enneadecagon 19
element 20 before sort: icosagon 20
element 21 before sort: hectogon 100
element 22 before sort: chiliagon 1000
element 23 before sort: myriagon 10000
▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒
element 1 after sort: ----polygon--- sides
element 2 after sort: ============== =======
element 3 after sort: chiliagon 1000
element 4 after sort: decagon 10
element 5 after sort: dodecagon 12
element 6 after sort: enneadecagon 19
element 7 after sort: hectogon 100
element 8 after sort: hendecagon 11
element 9 after sort: heptadecagon 17
element 10 after sort: heptagon 7
element 11 after sort: hexadecagon 16
element 12 after sort: hexagon 6
element 13 after sort: icosagon 20
element 14 after sort: myriagon 10000
element 15 after sort: nonagon 9
element 16 after sort: octadecagon 18
element 17 after sort: octagon 8
element 18 after sort: pentadecagon 15
element 19 after sort: pentagon 5
element 20 after sort: quadrilateral 4
element 21 after sort: tetradecagon 14
element 22 after sort: triangle 3
element 23 after sort: tridecagon 13
Ring
<lang ring> aList = [3,5,1,2,7,4,8,3,6,4,1] see combsort(aList)
func combsort t
gapd = 1.2473
gap = len(t)
swaps = 0
while gap + swaps > 1
k = 0
swaps = 0
if gap > 1 gap = floor(gap / gapd) ok
for k = 1 to len(t) - gap
if t[k] > t[k + gap]
temp = t[k]
t[k] = t[k + gap]
t[k + gap] = temp
swaps = swaps + 1 ok
next
end
return t
</lang>
Ruby
<lang ruby>class Array
def combsort!
gap = size
swaps = true
while gap > 1 or swaps
gap = [1, (gap / 1.25).to_i].max
swaps = false
0.upto(size - gap - 1) do |i|
if self[i] > self[i+gap]
self[i], self[i+gap] = self[i+gap], self[i]
swaps = true
end
end
end
self
end
end
p [23, 76, 99, 58, 97, 57, 35, 89, 51, 38, 95, 92, 24, 46, 31, 24, 14, 12, 57, 78].combsort!</lang> results in
[12, 14, 23, 24, 24, 31, 35, 38, 46, 51, 57, 57, 58, 76, 78, 89, 92, 95, 97, 99]
Rust
<lang rust>fn comb_sort<T: PartialOrd>(a: &mut [T]) {
let len = a.len();
let mut gap = len;
let mut swapped = true;
while gap > 1 || swapped {
gap = (4 * gap) / 5;
if gap < 1 {
gap = 1;
}
let mut i = 0;
swapped = false;
while i + gap < len {
if a[i] > a[i + gap] {
a.swap(i, i + gap);
swapped = true;
}
i += 1;
}
}
}
fn main() {
let mut v = vec![10, 8, 4, 3, 1, 9, 0, 2, 7, 5, 6];
println!("before: {:?}", v);
comb_sort(&mut v);
println!("after: {:?}", v);
}</lang>
- Output:
before: [10, 8, 4, 3, 1, 9, 0, 2, 7, 5, 6] after: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
Sather
<lang sather>class SORT{T < $IS_LT{T}} is
private swap(inout a, inout b:T) is temp ::= a; a := b; b := temp; end;
-- ---------------------------------------------------------------------------------
comb_sort(inout a:ARRAY{T}) is
gap ::= a.size;
swapped ::= true;
loop until!(gap <= 1 and ~swapped);
if gap > 1 then
gap := (gap.flt / 1.25).int;
end;
i ::= 0;
swapped := false;
loop until! ( (i + gap) >= a.size );
if (a[i] > a[i+gap]) then
swap(inout a[i], inout a[i+gap]); swapped := true; end;
i := i + 1;
end;
end;
end;
end;
class MAIN is
main is
a:ARRAY{INT} := |88, 18, 31, 44, 4, 0, 8, 81, 14, 78, 20, 76, 84, 33, 73, 75, 82, 5, 62, 70|;
b ::= a.copy;
SORT{INT}::comb_sort(inout b);
#OUT + b + "\n";
end;
end;</lang>
Scala
Imperative version (Ugly, side effects)
<lang Scala>object CombSort extends App {
val ia = Array(28, 44, 46, 24, 19, 2, 17, 11, 25, 4)
val ca = Array('X', 'B', 'E', 'A', 'Z', 'M', 'S', 'L', 'Y', 'C')
def sorted[E](input: Array[E])(implicit ord: Ordering[E]): Array[E] = {
import ord._
var gap = input.length
var swapped = true
while (gap > 1 || swapped) {
if (gap > 1) gap = (gap / 1.3).toInt
swapped = false
for (i <- 0 until input.length - gap)
if (input(i) >= input(i + gap)) {
val t = input(i)
input(i) = input(i + gap)
input(i + gap) = t
swapped = true
}
}
input
}
println(s"Unsorted : ${ia.mkString("[", ", ", "]")}")
println(s"Sorted : ${sorted(ia).mkString("[", ", ", "]")}\n")
println(s"Unsorted : ${ca.mkString("[", ", ", "]")}")
println(s"Sorted : ${sorted(ca).mkString("[", ", ", "]")}")
}</lang>
- Output:
See it in running in your browser by ScalaFiddle (JavaScript) or by Scastie (JVM).
Sidef
<lang ruby>func comb_sort(arr) {
var gap = arr.len;
var swaps = true;
while (gap > 1 || swaps) {
gap.div!(1.25).int! if (gap > 1);
swaps = false;
for i in ^(arr.len - gap) {
if (arr[i] > arr[i+gap]) {
arr[i, i+gap] = arr[i+gap, i];
swaps = true;
}
}
}
return arr;
}</lang>
Swift
<lang Swift>func combSort(inout list:[Int]) {
var swapped = true
var gap = list.count
while gap > 1 || swapped {
gap = gap * 10 / 13
if gap == 9 || gap == 10 {
gap = 11
} else if gap < 1 {
gap = 1
}
swapped = false
for var i = 0, j = gap; j < list.count; i++, j++ {
if list[i] > list[j] {
(list[i], list[j]) = (list[j], list[i])
swapped = true
}
}
}
}</lang>
Tcl
<lang tcl>proc combsort {input} {
set gap [llength $input]
while 1 {
set gap [expr {int(floor($gap / 1.3))}] set swaps 0 for {set i 0} {$i+$gap < [llength $input]} {incr i} { set j [expr {$i+$gap}] if {[lindex $input $i] > [lindex $input $j]} { set tmp [lindex $input $i] lset input $i [lindex $input $j] lset input $j $tmp incr swaps } } if {$gap <= 1 && !$swaps} break
} return $input
}
set data {23 76 99 58 97 57 35 89 51 38 95 92 24 46 31 24 14 12 57 78} puts [combsort $data]</lang> Produces this output:
12 14 23 24 24 31 35 38 46 51 57 57 58 76 78 89 92 95 97 99
TI-83 BASIC
Requires prgmSORTINS. Gap division of 1.3. Switches to Insertion sort when gap is less than 5.
:L1→L2 :dim(L2)→A :While A>5 and B=0 :int(A/1.3)→A :1→C :0→B :While (C+A)≥dim(L2) :If L2(C)>L2(C+A) :Then :L2(C)→D :L2(C+A)→L2(C) :D→L2(C+A) :1→B :End :C+1→C :End :DelVar A :DelVar B :DelVar C :DelVar D :L1→L3 :L2→L1 :prgmSORTINS :L3→L1 :DelVar L3 :Return
uBasic/4tH
<lang>PRINT "Comb sort:"
n = FUNC (_InitArray) PROC _ShowArray (n) PROC _Combsort (n) PROC _ShowArray (n)
END
_Combsort PARAM (1) ' Combsort subroutine
LOCAL(4) b@ = a@ c@ = 1
DO WHILE (b@ > 1) + c@
b@ = (b@ * 10) / 13
IF (b@ = 9) + (b@ = 10) THEN b@ = 11 IF b@ < 1 THEN b@ = 1
c@ = 0 d@ = 0 e@ = b@
DO WHILE e@ < a@
IF @(d@) > @(e@) THEN PROC _Swap (d@, e@) : c@ = 1
d@ = d@ + 1
e@ = e@ + 1
LOOP
LOOP
RETURN
_Swap PARAM(2) ' Swap two array elements
PUSH @(a@) @(a@) = @(b@) @(b@) = POP()
RETURN
_InitArray ' Init example array
PUSH 4, 65, 2, -31, 0, 99, 2, 83, 782, 1 FOR i = 0 TO 9 @(i) = POP() NEXT
RETURN (i)
_ShowArray PARAM (1) ' Show array subroutine
FOR i = 0 TO a@-1 PRINT @(i), NEXT PRINT
RETURN</lang>
VBA
{[trans|Phix}}<lang vb>Function comb_sort(ByVal s As Variant) As Variant
Dim gap As Integer: gap = UBound(s)
Dim swapped As Integer
Do While True
gap = WorksheetFunction.Max(WorksheetFunction.Floor_Precise(gap / 1.3), 1)
swapped = False
For i = 0 To UBound(s) - gap
si = Val(s(i))
If si > Val(s(i + gap)) Then
s(i) = s(i + gap)
s(i + gap) = CStr(si)
swapped = True
End If
Next i
If gap = 1 And Not swapped Then Exit Do
Loop
comb_sort = s
End Function
Public Sub main()
Dim s(9) As Variant
For i = 0 To 9
s(i) = CStr(Int(1000 * Rnd))
Next i
Debug.Print Join(s, ", ")
Debug.Print Join(comb_sort(s), ", ")
End Sub</lang>
- Output:
45, 414, 862, 790, 373, 961, 871, 56, 949, 364 45, 56, 364, 373, 414, 790, 862, 871, 949, 961
Wren
<lang ecmascript>var combSort = Fn.new { |a|
var gap = a.count
while (true) {
gap = (gap/1.25).floor
if (gap < 1) gap = 1
var i = 0
var swaps = false
while (true) {
if (a[i] > a[i+gap]) {
var t = a[i]
a[i] = a[i+gap]
a[i+gap] = t
swaps = true
}
i = i + 1
if (i + gap >= a.count) break
}
if (gap == 1 && !swaps) return
}
}
var as = [ [4, 65, 2, -31, 0, 99, 2, 83, 782, 1], [7, 5, 2, 6, 1, 4, 2, 6, 3] ] for (a in as) {
System.print("Before: %(a)")
combSort.call(a)
System.print("After : %(a)")
System.print()
}</lang>
- Output:
Before: [4, 65, 2, -31, 0, 99, 2, 83, 782, 1] After : [-31, 0, 1, 2, 2, 4, 65, 83, 99, 782] Before: [7, 5, 2, 6, 1, 4, 2, 6, 3] After : [1, 2, 2, 3, 4, 5, 6, 6, 7]
zkl
<lang zkl>fcn combSort(list){
len,gap,swaps:=list.len(),len,True;
while(gap>1 or swaps){
gap,swaps=(1).max(gap.toFloat()/1.2473), False;
foreach i in (len - gap){
if(list[i]>list[i + gap]){
list.swap(i,i + gap); swaps=True; }
} } list
}</lang> <lang zkl>combSort(List(28, 44, 46, 24, 19, 2, 17, 11, 25, 4)).println(); combSort("This is a test".toData()).text.println();</lang>
- Output:
L(2,4,11,17,19,24,25,28,44,46) Taehiissstt
- Clarified and Needing Review
- Programming Tasks
- Sorting Algorithms
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