Loops/N plus one half
Quite often one needs loops which, in the last iteration, execute only part of the loop body.
You are encouraged to solve this task according to the task description, using any language you may know.
- Goal
Demonstrate the best way to do this.
- Task
Write a loop which writes the comma-separated list
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
using separate output statements for the number and the comma from within the body of the loop.
- Related tasks
- Loop over multiple arrays simultaneously
- Loops/Break
- Loops/Continue
- Loops/Do-while
- Loops/Downward for
- Loops/For
- Loops/For with a specified step
- Loops/Foreach
- Loops/Increment loop index within loop body
- Loops/Infinite
- Loops/N plus one half
- Loops/Nested
- Loops/While
- Loops/with multiple ranges
- Loops/Wrong ranges
11l
<lang 11l>L(i) 1..10
print(i, end' ‘’) I !L.last_iteration print(‘, ’, end' ‘’)</lang>
360 Assembly
<lang 360asm>
- Loops/N plus one half 13/08/2015
LOOPHALF CSECT USING LOOPHALF,R12
LR R12,R15
BEGIN LA R3,MVC
SR R5,R5 LA R6,1 LA R7,10
LOOPI BXH R5,R6,ELOOPI for i=1 to 10
XDECO R5,XDEC MVC 0(4,R3),XDEC+8 LA R3,4(R3) CH R5,=H'10' BNL NEXTI MVC 0(2,R3),=C', ' LA R3,2(R3)
NEXTI B LOOPI next i ELOOPI XPRNT MVC,80
XR R15,R15 BR R14
MVC DC CL80' ' XDEC DS CL12
YREGS END LOOPHALF
</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
8086 Assembly
Since the output of the last element is different than the rest, the easiest way to accomplish this is by "breaking out" of the loop with a comparison to 10.
<lang asm> .model small
.stack 1024
.data ;no data needed .code
start: mov ax,0000h mov cx,0FFFFh ;this value doesn't matter as long as it's greater than decimal 10.
repeatPrinting: add ax,1 ;it was easier to start at zero and add here than to start at 1 and add after printing. aaa ;ascii adjust for addition, corrects 0009h+1 from 000Ah to 0100h call PrintBCD_IgnoreLeadingZeroes cmp ax,0100h ;does AX = BCD 10? je exitLoopEarly ;if so, we're done now. Don't finish the loop. push ax mov dl,"," ;print a comma mov ah,02h int 21h
mov dl,20h ;print a blank space mov ah,02h int 21h pop ax loop repeatPrinting exitLoopEarly: mov ax,4C00h int 21h ;return to DOS
PrintBCD_IgnoreLeadingZeroes: push ax cmp ah,0 jz skipLeadingZero or ah,30h ;converts a binary-coded-decimal value to an ASCII numeral push dx push ax mov al,ah mov ah,0Eh int 10h ;prints AL to screeen pop ax pop dx skipLeadingZero: or al,30h push dx push ax mov ah,0Eh int 10h ;prints AL to screen pop ax pop dx pop ax ret
end start ;EOF</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
AArch64 Assembly
<lang AArch64 Assembly> /* ARM assembly AARCH64 Raspberry PI 3B */ /* program loopnplusone64.s */
/*******************************************/ /* Constantes file */ /*******************************************/ /* for this file see task include a file in language AArch64 assembly*/ .include "../includeConstantesARM64.inc" /*********************************/ /* Initialized data */ /*********************************/ .data szMessResult: .asciz "@" // message result szMessComma: .asciz ", " szCarriageReturn: .asciz "\n" /*********************************/ /* UnInitialized data */ /*********************************/ .bss sZoneConv: .skip 24 /*********************************/ /* code section */ /*********************************/ .text .global main main: // entry of program
mov x20,1 // loop counter
1: // begin loop
mov x0,x20 ldr x1,qAdrsZoneConv // display value bl conversion10 // decimal conversion ldr x0,qAdrszMessResult ldr x1,qAdrsZoneConv // display value bl strInsertAtCharInc // insert result at @ character bl affichageMess // display message ldr x0,qAdrszMessComma bl affichageMess // display comma add x20,x20,1 // increment counter cmp x20,10 // end ? blt 1b // no ->begin loop one mov x0,x20 ldr x1,qAdrsZoneConv // display value bl conversion10 // decimal conversion ldr x0,qAdrszMessResult ldr x1,qAdrsZoneConv // display value bl strInsertAtCharInc // insert result at @ character bl affichageMess // display message ldr x0,qAdrszCarriageReturn bl affichageMess // display return line
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 qAdrszMessResult: .quad szMessResult qAdrszMessComma: .quad szMessComma qAdrszCarriageReturn: .quad szCarriageReturn
/********************************************************/ /* File Include fonctions */ /********************************************************/ /* for this file see task include a file in language AArch64 assembly */ .include "../includeARM64.inc" </lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
ACL2
ACL2 does not have loops, but this is close:
<lang Lisp>(defun print-list (xs)
(progn$ (cw "~x0" (first xs)) (if (endp (rest xs)) (cw (coerce '(#\Newline) 'string)) (progn$ (cw ", ") (print-list (rest xs))))))</lang>
Action!
<lang Action!>PROC Main()
BYTE i=[1] DO PrintB(i) IF i=10 THEN EXIT FI Print(", ") i==+1 OD
RETURN</lang>
- Output:
Screenshot from Atari 8-bit computer
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Ada
<lang ada>with Ada.Text_IO;
procedure LoopsAndHalf is begin
for i in 1 .. 10 loop Ada.Text_IO.put (i'Img); exit when i = 10; Ada.Text_IO.put (","); end loop; Ada.Text_IO.new_line;
end LoopsAndHalf;</lang>
Aime
<lang aime>integer i;
i = 0; while (1) {
i += 1; o_integer(i); if (i == 10) { break; } o_text(", ");
} o_text("\n");</lang>
ALGOL 60
<lang algol60>'BEGIN'
'COMMENT' Loops N plus one half - Algol60 - 20/06/2018; 'INTEGER' I; 'FOR' I:=1 'STEP' 1 'UNTIL' 10 'DO' 'BEGIN' OUTINTEGER(1,I); 'IF' I 'NOTEQUAL' 10 'THEN' OUTSTRING(1,'(', ')') 'END'
'END'</lang>
- Output:
+1 , +2 , +3 , +4 , +5 , +6 , +7 , +8 , +9 , +10
ALGOL 68
There are three common ways of achieving n+½ loops:
<lang algol68> FOR i WHILE
print(whole(i, -2));
print(", ") OD; print(new line)</lang> |
<lang algol68>FOR i TO 10 DO
print(whole(i, -2)); IF i < 10 THEN print(", ") FI OD; print(new line)</lang> |
<lang algol68>FOR i DO
print(whole(i, -2)); IF i >= 10 THEN GO TO done FI; print(", ") OD; done: print(new line)</lang> |
Output for all cases above:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
ALGOL W
<lang algolw>begin
integer i; i := 0; while begin i := i + 1; writeon( i ); i < 10 end do begin writeon( "," ) end
end.</lang>
AmigaE
<lang amigae>PROC main()
DEF i FOR i := 1 TO 10 WriteF('\d', i) EXIT i = 10 WriteF(', ') ENDFOR
ENDPROC</lang>
ARM Assembly
<lang ARM Assembly> /* ARM assembly Raspberry PI */ /* program loopnplusone.s */
/* Constantes */ .equ STDOUT, 1 @ Linux output console .equ EXIT, 1 @ Linux syscall .equ WRITE, 4 @ Linux syscall
/*********************************/ /* Initialized data */ /*********************************/ .data szMessResult: .ascii "" @ message result sMessValeur: .fill 11, 1, ' ' szMessComma: .asciz "," szCarriageReturn: .asciz "\n" /*********************************/ /* UnInitialized data */ /*********************************/ .bss /*********************************/ /* code section */ /*********************************/ .text .global main main: @ entry of program
mov r4,#1 @ loop counter
1: @ begin loop
mov r0,r4 ldr r1,iAdrsMessValeur @ display value bl conversion10 @ decimal conversion ldr r0,iAdrszMessResult bl affichageMess @ display message ldr r0,iAdrszMessComma bl affichageMess @ display comma add r4,#1 @ increment counter cmp r4,#10 @ end ? blt 1b @ no ->begin loop one mov r0,r4 ldr r1,iAdrsMessValeur @ display value bl conversion10 @ decimal conversion ldr r0,iAdrszMessResult bl affichageMess @ display message ldr r0,iAdrszCarriageReturn bl affichageMess @ display return line
100: @ standard end of the program
mov r0, #0 @ return code mov r7, #EXIT @ request to exit program svc #0 @ perform the system call
iAdrsMessValeur: .int sMessValeur iAdrszMessResult: .int szMessResult iAdrszMessComma: .int szMessComma iAdrszCarriageReturn: .int szCarriageReturn /******************************************************************/ /* 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
/******************************************************************/ /* Converting a register to a decimal */ /******************************************************************/ /* r0 contains value and r1 address area */ .equ LGZONECAL, 10 conversion10:
push {r1-r4,lr} @ save registers mov r3,r1 mov r2,#LGZONECAL
1: @ start loop
bl divisionpar10 @ r0 <- dividende. quotient ->r0 reste -> r1 add r1,#48 @ digit strb r1,[r3,r2] @ store digit on area sub r2,#1 @ previous position cmp r0,#0 @ stop if quotient = 0 bne 1b @ else loop @ end replaces digit in front of area mov r4,#0
2:
ldrb r1,[r3,r2] strb r1,[r3,r4] @ store in area begin add r4,#1 add r2,#1 @ previous position cmp r2,#LGZONECAL @ end ble 2b @ loop mov r1,#0 @ final zero strb r1,[r3,r4]
100:
pop {r1-r4,lr} @ restaur registres bx lr @return
/***************************************************/ /* division par 10 signé */ /* Thanks to http://thinkingeek.com/arm-assembler-raspberry-pi/* /* and http://www.hackersdelight.org/ */ /***************************************************/ /* r0 dividende */ /* r0 quotient */ /* r1 remainder */ divisionpar10:
/* r0 contains the argument to be divided by 10 */ push {r2-r4} @ save registers */ mov r4,r0 mov r3,#0x6667 @ r3 <- magic_number lower movt r3,#0x6666 @ r3 <- magic_number upper smull r1, r2, r3, r0 @ r1 <- Lower32Bits(r1*r0). r2 <- Upper32Bits(r1*r0) mov r2, r2, ASR #2 @ r2 <- r2 >> 2 mov r1, r0, LSR #31 @ r1 <- r0 >> 31 add r0, r2, r1 @ r0 <- r2 + r1 add r2,r0,r0, lsl #2 @ r2 <- r0 * 5 sub r1,r4,r2, lsl #1 @ r1 <- r4 - (r2 * 2) = r4 - (r0 * 10) pop {r2-r4} bx lr @ return
</lang>
ArnoldC
<lang arnoldc>IT'S SHOWTIME HEY CHRISTMAS TREE n YOU SET US UP @NO PROBLEMO HEY CHRISTMAS TREE lessThanTen YOU SET US UP @NO PROBLEMO STICK AROUND lessThanTen TALK TO THE HAND n GET TO THE CHOPPER lessThanTen HERE IS MY INVITATION 10 LET OFF SOME STEAM BENNET n ENOUGH TALK BECAUSE I'M GOING TO SAY PLEASE lessThanTen TALK TO THE HAND ", " YOU HAVE NO RESPECT FOR LOGIC GET TO THE CHOPPER n HERE IS MY INVITATION n GET UP @NO PROBLEMO ENOUGH TALK CHILL YOU HAVE BEEN TERMINATED</lang>
Arturo
<lang rebol>print join.with:", " map 1..10 => [to :string]</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
AutoHotkey
<lang AutoHotkey>Loop, 9 ; loop 9 times {
output .= A_Index ; append the index of the current loop to the output var If (A_Index <> 9) ; if it isn't the 9th iteration of the loop output .= ", " ; append ", " to the output var
} MsgBox, %output%</lang>
AutoIt
<lang autoit>#cs ----------------------------------------------------------------------------
AutoIt Version: 3.3.8.1 Author: Alexander Alvonellos
Script Function:
Output a comma separated list from 1 to 10, and on the tenth iteration of the output loop, only perform half of the loop.
- ce ----------------------------------------------------------------------------
Func doLoopIterative() Dim $list = "" For $i = 1 To 10 Step 1 $list = $list & $i If($i = 10) Then ExitLoop $list = $list & ", " Next return $list & @CRLF EndFunc
Func main() ConsoleWrite(doLoopIterative()) EndFunc
main()</lang>
AWK
One-liner: <lang awk>$ awk 'BEGIN{for(i=1;i<=10;i++){printf i;if(i<10)printf ", "};print}'</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Readable version: <lang awk> BEGIN {
n=10 for(i=1;i<=n;i++) { printf i; if(i<n) printf ", " } print
}</lang> Same output.
Axe
<lang axe>For(I,1,10)
Disp I▶Dec If I=10 Disp i Else Disp "," End
End</lang>
BASIC
<lang qbasic>DIM i AS Integer
FOR i=1 TO 10
PRINT i; IF i=10 THEN EXIT FOR PRINT ", ";
NEXT i</lang>
Applesoft BASIC
The ZX Spectrum Basic code will work just fine in Applesoft BASIC. The following is a more structured approach which avoids the use of GOTO.
<lang ApplesoftBasic>10 FOR I = 1 TO 10 20 PRINT I; 30 IF I < 10 THEN PRINT ", "; : NEXT I</lang>
IS-BASIC
<lang IS-BASIC>100 FOR I=1 TO 10 110 PRINT I; 120 IF I=10 THEN EXIT FOR 130 PRINT ","; 140 NEXT</lang>
Sinclair ZX81 BASIC
The ZX Spectrum Basic program will work on the ZX81. Depending on the context, the programmer's intention may be clearer if we do it all with GOTO
s instead of a FOR
loop.
<lang basic>10 LET I=1
20 PRINT I;
30 IF I=10 THEN GOTO 70
40 PRINT ", ";
50 LET I=I+1
60 GOTO 20</lang>
ZX Spectrum Basic
To terminate a loop on the ZX Spectrum, set the loop counter to a value that will exit the loop, before jumping to the NEXT statement.
<lang zxbasic>10 FOR i=1 TO 10 20 PRINT i; 30 IF i=10 THEN GOTO 50 40 PRINT ", "; 50 NEXT i</lang>
Basic09
<lang basic09> PROCEDURE nAndAHalf
DIM i:INTEGER FOR i:=1 TO 10 PRINT i; EXITIF i=10 THEN ENDEXIT PRINT ", "; NEXT i PRINT
</lang>
BASIC256
<lang BASIC256>for i = 1 to 10 print i; if i < 10 then print ", "; next i
end</lang>
BBC BASIC
<lang bbcbasic> FOR i% = 1 TO 10
PRINT ; i% ; IF i% <> 10 PRINT ", "; NEXT PRINT</lang>
True BASIC
<lang qbasic>LET cm$ = "" FOR i = 1 to 10
PRINT cm$; str$(i); LET cm$ = ", "
NEXT i END</lang>
bc
The print
extension is necessary to get the required output.
<lang bc>while (1) {
print ++i if (i == 10) { print "\n" break } print ", "
}</lang>
Befunge
<lang befunge>1+>::.9`#@_" ,",,</lang> This code is a good answer. However, most Befunge implementations print a " " after using . (output number), so this program prints "1 , 2 , 3 ..." with extra spaces. A bypass for this is possible, by adding 48 and printing the ascii character, but does not work with 10:: <lang befunge>1+>::68*+,8`#v_" ,",,
@,,,,", 10"<</lang>
Bracmat
<lang bracmat> 1:?i & whl
' ( put$!i & !i+1:~>10:?i & put$", " )</lang>
C
<lang c>#include <stdio.h>
int main() {
int i; for (i = 1; i <= 10; i++) { printf("%d", i); printf(i == 10 ? "\n" : ", "); } return 0;
}</lang>
C#
<lang csharp>using System;
class Program {
static void Main(string[] args) { for (int i = 1; ; i++) { Console.Write(i); if (i == 10) break; Console.Write(", "); } Console.WriteLine(); }
}</lang>
C++
<lang cpp>#include <iostream>
int main() {
int i; for (i = 1; i<=10 ; i++){ std::cout << i; if (i < 10) std::cout << ", "; } return 0;
} </lang>
Chapel
<lang chapel>for i in 1..10 do
write(i, if i % 10 > 0 then ", " else "\n")</lang>
Clojure
<lang clojure>
- Functional version
(apply str (interpose ", " (range 1 11)))
- Imperative version
(loop [n 1]
(printf "%d" n) (if (< n 10) (do
(print ", ") (recur (inc n))))) </lang>
COBOL
<lang cobol> IDENTIFICATION DIVISION.
PROGRAM-ID. Loop-N-And-Half.
DATA DIVISION. WORKING-STORAGE SECTION. 01 I PIC 99. 01 List PIC X(45).
PROCEDURE DIVISION. PERFORM FOREVER *> The list to display must be built up because using *> DISPLAY adds an endline at the end automatically. STRING FUNCTION TRIM(List) " " I INTO List
IF I = 10 EXIT PERFORM END-IF STRING FUNCTION TRIM(List) "," INTO List
ADD 1 TO I END-PERFORM
DISPLAY List
GOBACK .</lang>
Free-form, 'List'-free version, using DISPLAY NO ADVANCING. <lang cobol>IDENTIFICATION DIVISION. PROGRAM-ID. LOOP-1p5-NOADV. DATA DIVISION. WORKING-STORAGE SECTION. 01 I PIC 99 VALUE 1. 01 IDISP PIC Z9. PROCEDURE DIVISION. PERFORM FOREVER MOVE I TO IDISP DISPLAY FUNCTION TRIM(IDISP) WITH NO ADVANCING IF I = 10 EXIT PERFORM END-IF DISPLAY ", " WITH NO ADVANCING ADD 1 TO I END-PERFORM. STOP RUN. END-PROGRAM.</lang> Free-form, GO TO, 88-level. Paragraphs in PROCEDURE DIVISION. <lang cobol>IDENTIFICATION DIVISION. PROGRAM-ID. LOOP-1p5-NOADV-GOTO. DATA DIVISION. WORKING-STORAGE SECTION. 01 I PIC 99 VALUE 1. 88 END-LIST VALUE 10. 01 I-OUT PIC Z9. PROCEDURE DIVISION. 01-LOOP. MOVE I TO I-OUT. DISPLAY FUNCTION TRIM(I-OUT) WITH NO ADVANCING. IF END-LIST GO TO 02-DONE. DISPLAY ", " WITH NO ADVANCING. ADD 1 TO I. GO TO 01-LOOP. 02-DONE. STOP RUN. END-PROGRAM.</lang> Using 'PERFORM VARYING' <lang cobol>IDENTIFICATION DIVISION. PROGRAM-ID. LOOP-1p5-NOADV-VARY. DATA DIVISION. WORKING-STORAGE SECTION. 01 I PIC 99 VALUE 1. 88 END-LIST VALUE 10. 01 I-OUT PIC Z9. PROCEDURE DIVISION. PERFORM WITH TEST AFTER VARYING I FROM 1 BY 1 UNTIL END-LIST MOVE I TO I-OUT DISPLAY FUNCTION TRIM(I-OUT) WITH NO ADVANCING IF NOT END-LIST DISPLAY ", " WITH NO ADVANCING END-IF END-PERFORM. STOP RUN. END-PROGRAM.</lang>
CoffeeScript
<lang coffeescript>
- Loop plus half. This code shows how to break out of a loop early
- on the last iteration. For the contrived example, there are better
- ways to generate a comma-separated list, of course.
start = 1 end = 10 s = for i in [start..end]
# the top half of the loop executes every time s += i break if i == end # the bottom half of the loop is skipped for the last value s += ', '
console.log s </lang>
ColdFusion
With tags: <lang cfm><cfloop index = "i" from = "1" to = "10">
#i# <cfif i EQ 10> <cfbreak /> </cfif> ,
</cfloop></lang>
With script: <lang cfm><cfscript>
for( i = 1; i <= 10; i++ ) //note: the ++ notation works only on version 8 up, otherwise use i=i+1 { writeOutput( i ); if( i == 10 ) { break; } writeOutput( ", " ); }
</cfscript></lang>
Common Lisp
<lang lisp> (loop for i from 1 below 10 do
(princ i) (princ ", ") finally (princ i))
</lang>
or
<lang lisp>(loop for i from 1 upto 10 do
(princ i) (if (= i 10) (return)) (princ ", "))</lang>
but for such simple tasks we can use format's powers:
<lang lisp> (format t "~{~a~^, ~}" (loop for i from 1 to 10 collect i)) </lang>
Using DO
<lang lisp> (do ((i 1 (incf i))) ; Initialize to 1 and increment on every loop
((> i 10)) ; Break condition (princ i) ; Print the iteration number (when (= i 10) (go end)) ; Use the implicit tagbody and go to end tag when reach the last iteration (princ ", ") ; Printing the comma is jumped by the go statement end) ; The tag
</lang> or <lang lisp> (do ; Not exactly separate statements for the number and the comma
((i 1 (incf i))) ; Initialize to 1 and increment on every loop ((> i 9) (princ i)) ; Break condition when iteration is the last number, print it (princ i) ; Print number statement (princ ", ")) ; Print comma statement
</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Cowgol
<lang cowgol>include "cowgol.coh";
var i: uint8 := 1; loop
print_i8(i); if i == 10 then break; end if; print(", "); i := i + 1;
end loop; print_nl();</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
D
Iterative
<lang d>import std.stdio;
void main() {
for (int i = 1; ; i++) { write(i); if (i >= 10) break; write(", "); }
writeln();
}</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Functional Style
<lang d>void main() {
import std.stdio, std.range, std.algorithm, std.conv, std.string; iota(1, 11).map!text.join(", ").writeln;
// A simpler solution: writefln("%(%d, %)", iota(1, 11));
}</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Dart
<lang Dart>String loopPlusHalf(start, end) {
var result = ; for(int i = start; i <= end; i++) { result += '$i'; if(i == end) { break; } result += ', '; } return result;
}
void main() {
print(loopPlusHalf(1, 10));
}</lang>
Delphi
<lang Delphi>program LoopsNPlusOneHalf;
{$APPTYPE CONSOLE}
var
i: integer;
const
MAXVAL = 10;
begin
for i := 1 to MAXVAL do begin Write(i); if i < MAXVAL then Write(', '); end; Writeln;
end.</lang>
Draco
<lang draco>proc nonrec main() void:
byte i; i := 1; while write(i); i := i + 1; i <= 10 do write(", ") od
corp</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
DWScript
<lang Delphi>var i : Integer;
for i := 1 to 10 do begin
Print(i); if i < 10 then Print(', ');
end;</lang>
E
A typical loop+break solution: <lang e>var i := 1 while (true) {
print(i) if (i >= 10) { break } print(", ") i += 1
}</lang>
Using the loop primitive in a semi-functional style:
<lang e>var i := 1 __loop(fn {
print(i) if (i >= 10) { false } else { print(", ") i += 1 true }
})</lang>
EchoLisp
<lang lisp> (string-delimiter "")
(for ((i (in-range 1 11))) (write i) #:break (= i 10) (write ","))
→ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10
- or
(string-join (range 1 11) ",")
→ 1,2,3,4,5,6,7,8,9,10
</lang>
EDSAC order code
<lang edsac>[ N and a half times loop
=======================
A program for the EDSAC
Works with Initial Orders 2 ]
T56K GK
O16@
[ 1 ] T24@
A25@ A18@ U25@ S23@ E11@
O25@ O19@ O20@ G1@
[ 11 ] O18@
O17@ O21@ O22@ ZF
[ 16 ] #F [ 17 ] PF [ 18 ] QF [ 19 ] NF [ 20 ] !F [ 21 ] @F [ 22 ] &F [ 23 ] JF [ 24 ] PF [ 25 ] PF
EZPF</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Elixir
<lang elixir>defmodule Loops do
def n_plus_one_half([]), do: IO.puts "" def n_plus_one_half([x]), do: IO.puts x def n_plus_one_half([h|t]) do IO.write "#{h}, " n_plus_one_half(t) end
end
Enum.to_list(1..10) |> Loops.n_plus_one_half</lang>
Erlang
<lang erlang>%% Implemented by Arjun Sunel -module(loop). -export([main/0]).
main() -> for_loop(1).
for_loop(N) -> if N < 10 ->
io:format("~p, ",[N] ), for_loop(N+1); true -> io:format("~p\n",[N]) end. </lang>
ERRE
<lang ERRE> FOR I=1 TO 10 DO
PRINT(I;) EXIT IF I=10 PRINT(", ";)
END FOR </lang>
Euphoria
<lang Euphoria> for i = 1 to 10 do
printf(1, "%g", {i}) if i < 10 then puts(1, ", ") end if
end for </lang>
While, yes, use of exit
would also work here, it is slightly faster to code it this way, if only the last iteration has something different.
F#
Functional version that works for lists of any length <lang fsharp> let rec print (lst : int list) =
match lst with | hd :: [] -> printf "%i " hd | hd :: tl -> printf "%i, " hd print tl | [] -> printf "\n"
print [1..10] </lang>
Factor
<lang factor>: print-comma-list ( n -- )
[ [1,b] ] keep '[ [ number>string write ] [ _ = [ ", " write ] unless ] bi ] each nl ;</lang>
Falcon
<lang falcon>for value = 1 to 10
formiddle >> value >> ", " end forlast: > value
end</lang>
- Output:
prompt$ falcon forto.fal 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
FALSE
<lang false>1[$9>~][$.", "1+]#.</lang>
Fantom
<lang fantom> class Main {
public static Void main () { for (Int i := 1; i <= 10; i++) { Env.cur.out.writeObj (i) if (i == 10) break Env.cur.out.writeChars (", ") } Env.cur.out.printLine ("") }
} </lang>
FBSL
<lang qbasic>
- APPTYPE CONSOLE
For Dim i = 1 To 10
PRINT i; IF i < 10 THEN PRINT ", ";
Next PAUSE</lang> Output
1, 2, 3, 4, 5, 6, 7, 8, 9, 10 Press any key to continue...
Forth
<lang forth>: comma-list ( n -- )
dup 1 ?do i 1 .r ." , " loop . ;</lang>
<lang forth>: comma-list ( n -- )
dup 1+ 1 do i 1 .r dup i = if leave then \ or DROP UNLOOP EXIT to exit loop and the function [char] , emit space loop drop ;</lang>
<lang forth>: comma-list ( n -- )
1 begin dup 1 .r 2dup <> while ." , " 1+ repeat 2drop ;</lang>
Fortran
<lang fortran>C Loops N plus one half - Fortran IV (1964)
INTEGER I WRITE(6,301) (I,I=1,10) 301 FORMAT((I3,',')) END</lang>
<lang fortran>C WARNING: This program is not valid ANSI FORTRAN 77 code. It uses C two nonstandard characters on the lines labelled 5001 and 5002. C Many F77 compilers should be okay with it, but it is *not* C standard.
PROGRAM LOOPPLUSONEHALF INTEGER I, TEN
C I'm setting a parameter to distinguish from the label 10.
PARAMETER (TEN = 10)
DO 10 I = 1, TEN
C Write the number only.
WRITE (*,5001) I
C If we are on the last one, stop here. This will make this test C every iteration, which can slow your program down a little. If C you want to speed this up at the cost of your own convenience, C you could loop only to nine, and handle ten on its own after C the loop is finished. If you don't care, power to you.
IF (I .EQ. TEN) GOTO 10
C Append a comma to the number.
WRITE (*,5002) ',' 10 CONTINUE
C Always finish with a newline. This programmer hates it when a C program does not end its output with a newline.
WRITE (*,5000) STOP
5000 FORMAT (A)
C Standard FORTRAN 77 is completely incapable of completing a C WRITE statement without printing a newline. This program would C be much more difficult (i.e. impossible) to write in the ANSI C standard, without cheating and saying something like: C C WRITE (*,*) '1, 2, 3, 4, 5, 6, 7, 8, 9, 10' C C The dollar sign at the end of the format is a nonstandard C character. It tells the compiler not to print a newline. If you C are actually using FORTRAN 77, you should figure out what your C particular compiler accepts. If you are actually using Fortran C 90 or later, you should replace this line with the commented C line that follows it.
5001 FORMAT (I3, $) 5002 FORMAT (A, $)
C5001 FORMAT (T3, ADVANCE='NO') C5001 FORMAT (A, ADVANCE='NO')
END</lang>
<lang fortran>i = 1 do
write(*, '(I0)', advance='no') i if ( i == 10 ) exit write(*, '(A)', advance='no') ', ' i = i + 1
end do write(*,*)</lang>
FreeBASIC
<lang freebasic>' FB 1.05.0 Win64
For i As Integer = 1 To 10
Print Str(i); If i < 10 Then Print ", ";
Next
Print Sleep</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Alternative
This makes the important point that for many loops of this kind the partial iteration could easily be the first one.
<lang freebasic>dim as string cm = "" for i as ubyte = 1 to 10
print cm;str(i); cm = ", "
next i</lang>
FutureBasic
<lang futurebasic>window 1
long i, num = 10
for i = 1 to num
print i; if i = num then break print @", ";
next i
HandleEvents</lang> Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Gambas
Click this link to run this code <lang gambas>Public Sub Main() Dim siLoop As Short
For siLoop = 1 To 10
Print siLoop; If siLoop <> 10 Then Print ", ";
Next
End</lang> Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
GAP
<lang gap>n := 10; for i in [1 .. n] do
Print(i); if i < n then Print(", "); else Print("\n"); fi;
od;</lang>
GML
<lang GML>str = "" for(i = 1; i <= 10; i += 1)
{ str += string(i) if(i != 10) str += ", " }
show_message(str)</lang>
Go
<lang go>package main
import "fmt"
func main() {
for i := 1; ; i++ { fmt.Print(i) if i == 10 { fmt.Println() break } fmt.Print(", ") }
}</lang>
Gosu
<lang java>var out = System.out for(i in 1..10) {
if(i > 1) out.print(", ") out.print(i)
}</lang>
Groovy
Solution: <lang groovy>for(i in (1..10)) {
print i if (i == 10) break print ', '
}</lang>
Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
GW-BASIC
<lang gwbasic>10 C$ = "" 20 FOR I = 1 TO 10 30 PRINT C$;STR$(I); 40 C$=", " 50 NEXT I</lang>
Haskell
<lang haskell>main :: IO () main = forM_ [1 .. 10] $ \n -> do
putStr $ show n putStr $ if n == 10 then "\n" else ", "</lang>
You can also use intersperse :: a -> [a] -> [a] <lang haskell>intercalate ", " (map show [1..10])</lang>
Haxe
<lang haxe>for (i in 1...11)
Sys.print('$i${i == 10 ? '\n' : ', '}');</lang>
hexiscript
<lang hexiscript>for let i 1; i <= 10; i++
print i if i = 10; break; endif print ", "
endfor println ""</lang>
HicEst
<lang hicest>DO i = 1, 10
WRITE(APPend) i IF(i < 10) WRITE(APPend) ", "
ENDDO</lang>
HolyC
<lang holyc>U8 i, max = 10; for (i = 1; i <= max; i++) {
Print("%d", i); if (i == max) break; Print(", ");
} Print("\n");</lang>
Icon and Unicon
<lang Icon>procedure main() every writes(i := 1 to 10) do
if i = 10 then break write() else writes(", ")
end</lang>
The above can be written more succinctly as: <lang Icon>every writes(c := "",1 to 10) do c := "," </lang>
IDL
Nobody would ever use a loop in IDL to output a vector of numbers - the requisite output would be generated something like this:
<lang idl>print,indgen(10)+1,format='(10(i,:,","))'</lang>
However if a loop had to be used it could be done like this:
<lang idl>for i=1,10 do begin
print,i,format='($,i)' if i lt 10 then print,",",format='($,a)'
endfor</lang>
(which merely suppresses the printing of the comma in the last iteration);
or like this:
<lang idl>for i=1,10 do begin
print,i,format='($,i)' if i eq 10 then break print,",",format='($,a)'
end</lang>
(which terminates the loop early if the last element is reached).
J
<lang j>output=: verb define
buffer=: buffer,y
)
loopy=: verb define
buffer=: for_n. 1+i.10 do. output ":n if. n<10 do. output ', ' end. end. smoutput buffer
)</lang>
Example use: <lang j> loopy 0 1, 2, 3, 4, 5, 6, 7, 8, 9, 10</lang>
That said, note that neither loops nor output statements are necessary:
<lang j> ;}.,(', ' ; ":)&> 1+i.10 1, 2, 3, 4, 5, 6, 7, 8, 9, 10</lang>
And, note also that this sort of data driven approach can also deal with more complex issues:
<lang j> commaAnd=: ":&.> ;@,. -@# {. (<;._1 '/ and /') ,~ (<', ') #~ #
commaAnd i.5
0, 1, 2, 3 and 4</lang>
Java
<lang java>public static void main(String[] args) {
for (int i = 1; ; i++) { System.out.print(i); if (i == 10) break; System.out.print(", "); } System.out.println();
}</lang>
JavaScript
<lang javascript>function loop_plus_half(start, end) {
var str = , i; for (i = start; i <= end; i += 1) { str += i; if (i === end) { break; } str += ', '; } return str;
}
alert(loop_plus_half(1, 10));</lang>
Alternatively, if we stand back for a moment from imperative assumptions about the nature and structure of computing tasks, it becomes clear that the problem of special transitional cases as a pattern terminates has no necessary connection with loops. (See the comments accompanying the ACL2, Haskell, IDL, J and R examples above and below, and see also some of the approaches taken in languages like Clojure and Scala.
If a JavaScript expression evaluates to an array [1 .. 10] of integers, for example, we can map that array directly to a comma-delimited string by using the Array.join() function, writing something like:
<lang JavaScript>function range(m, n) {
return Array.apply(null, Array(n - m + 1)).map( function (x, i) { return m + i; } );
}
console.log(
range(1, 10).join(', ')
);</lang>
Output: <lang JavaScript>1, 2, 3, 4, 5, 6, 7, 8, 9, 10</lang>
Otherwise, any special transitional case at the end of a pattern can be handled by defining conditional values for one or more sub-expressions:
<lang JavaScript>function range(m, n) {
return Array.apply(null, Array(n - m + 1)).map(function (x, i) { return m + i; });
}
console.log(
(function (nFrom, nTo) { var iLast = nTo - 1;
return range(nFrom, nTo).reduce( function (accumulator, n, i) { return accumulator + n.toString() +
(i < iLast ? ', ' : ); // conditional sub-expression
}, ) })(1, 10)
);</lang>
Output: <lang JavaScript>1, 2, 3, 4, 5, 6, 7, 8, 9, 10</lang>
Otherwise
<lang JavaScript>var s=1, e=10 for (var i=s; i<=e; i+=1) { document.write( i==s ? : ', ', i ) }</lang> or <lang JavaScript>var s=1, e=10 for (;; s+=1) { document.write( s ) if (s==e) break document.write( ', ' ) }</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
jq
In jq, it is idiomatic to view a range of integers with boundaries m and n as [m, n), i.e. including m but excluding n. <lang jq>One approach is to construct the answer incrementally: def loop_plus_half(m;n):
if m<n then reduce range(m+1;n) as $i (m|tostring; . + ", " + ($i|tostring)) else empty end;
- An alternative that is shorter and perhaps closer to the task description because it uses range(m;n) is as follows:
def loop_plus_half2(m;n):
[range(m;n) | if . == m then . else ", ", . end | tostring] | join("");</lang>
- Output:
loop_plus_half2(1;11) # "1, 2, 3, 4, 5, 6, 7, 8, 9, 10"
Julia
The short-circuiting && is idiomatic to Julia - the second expression will only be evaluated if the first one is true. <lang Julia> for i = 1:10
print(i) i == 10 && break print(", ")
end </lang> Output: <lang Julia> 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 </lang>
K
<lang K> p:{`0:$x} / output
i:1;do[10;p[i];p[:[i<10;", "]];i+:1];p@"\n"
1, 2, 3, 4, 5, 6, 7, 8, 9, 10</lang>
Alternative solutions: <lang K> 10 {p@x;p@:[x<10;", ";"\n"];x+1}\1;
{p@x;p@:[x<10;", ";"\n"];x+1}'1+!10; /variant</lang>
Kotlin
<lang scala>// version 1.0.6
fun main(args: Array<String>) {
for (i in 1 .. 10) { print(i) if (i < 10) print(", ") }
}</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
LabVIEW
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.
Lambdatalk
<lang scheme> {def loops_N_plus_one_half
{lambda {:i :n} {if {> :i :n} then (end of loop with a dot) else {if {= :i 6} then {br}:i else :i}{if {= :i :n} then . else ,} {loops_N_plus_one_half {+ :i 1} :n}}}}
-> loops_N_plus_one_half
{loops_N_plus_one_half 0 10} -> 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. (end of loop with a dot) </lang>
Lang5
<lang lang5>: , dup ", " 2 compress "" join ; 1 do dup 10 != if dup , . 1 + else . break then loop</lang> Word: Loops/For#Lang5 <lang lang5>: 2string 2 compress "" join ;
- , dup 10 != if ", " 2string then ;
1 10 "dup , . 1+" times</lang>
Lasso
<lang Lasso>local(out) = loop(10) => {
#out->append(loop_count) loop_count == 10 ? loop_abort #out->append(', ')
}
- out</lang>
Lhogho
type
doesn't output a newline. The print
outputs one.
<lang logo>for "i [1 10]
[
type :i
if :i < 10
[
type "|, |
]
]
print</lang>
A more list-y way of doing it
<lang logo>to join :lst :sep if list? :lst [ ifelse count :lst > 1 [ op (word first :lst :sep joinWith butfirst :lst :sep) ] [ op (word last :lst) ] ] op :lst end
make "aList [1 2 3 4 5 6 7 8 9 10] print join :aList "|, |</lang>
Liberty BASIC
Keyword 'exit' allows the termination. <lang lb> for i =1 to 10
print i; if i =10 then exit for print ", ";
next i end </lang>
Lisaac
<lang Lisaac>Section Header
+ name := LOOP_AND_HALF;
Section Public
- main <- (
+ i : INTEGER;
i := 1; { i.print; i = 10 }.until_do { ", ".print; i := i + 1; }; '\n'.print;
);</lang>
LiveCode
<lang LiveCode>repeat with n = 1 to 10
put n after loopn if n is not 10 then put comma after loopn
end repeat put loopn</lang>
Logo
<lang logo>to comma.list :n
repeat :n-1 [type repcount type "|, |] print :n
end
comma.list 10</lang>
Lua
Translation of C: <lang lua>for i = 1, 10 do
io.write(i) if i == 10 then break end io.write", "
end</lang>
M2000 Interpreter
<lang M2000 Interpreter> Module Checkit {
\\ old type loop For i=1 to 10 Print i; If i=10 Then Exit For Print ", "; Next i Print \\ fast type loop. Continue exit block, without breaking loop. For i=1 to 10 { Print i; If i=10 Then Continue Print ", "; } Print Print i=0 { loop \\ this mark block for loop, each time need to mark i++ Print i; If i=10 Then Exit ' so now we use exit to break loop Print ", "; } Print
} Checkit </lang>
M4
<lang M4>define(`break',
`define(`ulim',llim)')
define(`for',
`ifelse($#,0,``$0, `define(`ulim',$3)`'define(`llim',$2)`'ifelse(ifelse($3,`',1, `eval($2<=$3)'),1, `pushdef(`$1',$2)$4`'popdef(`$1')$0(`$1',incr($2),ulim,`$4')')')')
for(`x',`1',`',
`x`'ifelse(x,10,`break',`, ')')</lang>
Make
<lang make>NEXT=`expr $* + 1` MAX=10 RES=1
all: 1-n;
$(MAX)-n:
@echo $(RES)
%-n:
@-make -f loop.mk $(NEXT)-n MAX=$(MAX) RES=$(RES),$(NEXT)</lang>
Invoking it
|make -f loop.mk MAX=10 1,2,3,4,5,6,7,8,9,10
Maple
<lang Maple>> for i to 10 do printf( "%d%s", i, `if`( i = 10, "\n", ", " ) ) end: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10</lang>
Mathematica/Wolfram Language
<lang Mathematica>i = 1; s = ""; While[True,
s = s <> ToString@i; If[i == 10, Break[]]; s = s <> ","; i++; ]
s</lang>
MATLAB / Octave
Vectorized form: <lang MATLAB> printf('%i, ',1:9); printf('%i\n',10);</lang>
Explicite loop: <lang Matlab> for k=1:10,
printf('%i', k); if k==10, break; end; printf(', '); end; printf('\n');</lang>
Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
MAXScript
<lang maxscript>for i in 1 to 10 do (
format "%" i if i == 10 then exit format "%" ", "
)</lang>
Metafont
Since message append always a newline, we need building the output inside a string, and then we output it.
<lang metafont>last := 10; string s; s := ""; for i = 1 upto last:
s := s & decimal i; if i <> last: s := s & ", " fi;
endfor message s; end</lang>
Microsoft Small Basic
<lang smallbasic>For i = 1 To 10
TextWindow.Write(i) If i <> 10 Then TextWindow.Write(", ") EndIf
EndFor TextWindow.WriteLine("")</lang>
min
min's linrec
combinator is flexible enough to easily accomodate this task, due to taking a quotation to execute at the end of the loop (the second one).
<lang min>1 (dup 10 ==) 'puts! (print succ ", " print!) () linrec</lang>
Modula-3
<lang modula3>MODULE Loop EXPORTS Main;
IMPORT IO, Fmt;
VAR i := 1;
BEGIN
LOOP IO.Put(Fmt.Int(i)); IF i = 10 THEN EXIT; END; IO.Put(", "); i := i + 1; END; IO.Put("\n");
END Loop.</lang>
MUMPS
<lang MUMPS>LOOPHALF
NEW I FOR I=1:1:10 DO .WRITE I .IF I'=10 WRITE ", " QUIT ;Alternate NEW I FOR I=1:1:10 WRITE I WRITE:I'=10 ", " KILL I QUIT</lang>
Output:
USER>D LOOPHALF^ROSETTA 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 USER>D LOOPHALF+7^ROSETTA 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Nemerle
<lang Nemerle>foreach (i in [1 .. 10]) {
Write(i); unless (i == 10) Write(", ");
}</lang>
NetRexx
<lang NetRexx>/* NetRexx */ /* NetRexx */ options replace format comments java crossref savelog symbols nobinary
say say 'Loops/N plus one half'
rs = istart = 1 iend = 10 loop i_ = istart to iend rs = rs || ' ' || i_ if i_ < iend then do rs = rs',' end end i_ say rs.strip()</lang>
Output
Loops/N plus one half 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
NewLISP
<lang NewLISP>(for (i 0 10)
(print i) (unless (= i 10) (print ", ")))</lang>
Nim
<lang nim>var s = "" for i in 1..10:
s.add $i if i == 10: break s.add ", "
echo s</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
NS-HUBASIC
<lang NS-HUBASIC>10 FOR I=1 TO 10 20 PRINT I; 30 IF I=10 THEN GOTO 50 40 PRINT ","; 50 NEXT</lang>
Objeck
<lang objeck> bundle Default {
class Hello { function : Main(args : String[]) ~ Nil { for(i := 1; true; i += 1;) { i->Print(); if(i = 10) { break; }; ", "->Print(); }; '\n'->Print(); } }
} </lang>
OCaml
<lang ocaml>let last = 10 in for i = 1 to last do
print_int i; if i <> last then print_string ", ";
done; print_newline();</lang>
<lang ocaml>let ints = [1; 2; 3; 4; 5; 6; 7; 8; 9; 10] in let str_ints = List.map string_of_int ints in print_endline (String.concat ", " str_ints);</lang>
Oforth
<lang Oforth>: loopn | i |
10 loop: i [ i dup print 10 ifEq: [ break ] "," . ] printcr ;</lang>
Oz
Using a for-loop: <lang oz> for N in {List.number 1 10 1} break:Break do
{System.printInfo N} if N == 10 then {Break} end {System.printInfo ", "}
end</lang>
However, it seems more natural to use a left fold: <lang oz>declare
fun {CommaSep Xs} case Xs of nil then nil [] X|Xr then
{FoldL Xr fun {$ Z X} Z#", "#X end X}
end end
in
{System.showInfo {CommaSep {List.number 1 10 1}}}</lang>
Panda
Panda is stream based. To know if there is no more values you need to know it's the last. You can only do that if you get all the values. So this is functional style; We accumulate all the values from the stream. Then join them together as strings with a comma. <lang panda>arrayTemplate:1..10.join(',')</lang>
PARI/GP
<lang parigp>n=0; while(1,
print1(n++); if(n>9, break); print1(", ")
);</lang>
Pascal
<lang pascal>program numlist(output);
const MAXNUM: integer = 10; var
i: integer;
begin
{ loop 1: w/ if branching } for i := 1 to MAXNUM do begin write(i); if i <> MAXNUM then write(', ') end; writeln; { loop 2: w/o if branching } for i := 1 to MAXNUM-1 do write(i, ', '); writeln(MAXNUM);
end.</lang>
Peloton
<lang sgml><@ FORLITLIT>10|<@ SAYPOSFOR>...</@><@ ABF>,</@></@></lang>
Perl
<lang perl>for my $i(1..10) {
print $i; last if $i == 10; print ', ';
} print "\n";</lang>
In perl one would solve the task via join
.
<lang perl>print join(', ', 1..10), "\n";</lang>
Phix
for i=1 to 10 do printf(1,"%d",i) if i=10 then exit end if printf(1,", ") end for
PHP
<lang php>for ($i = 1; $i <= 11; $i++) {
echo $i; if ($i == 10) break; echo ', ';
} echo "\n";</lang>
PicoLisp
<lang PicoLisp>(for N 10
(prin N) (T (= N 10)) (prin ", ") )</lang>
Pike
<lang pike> int main(){
for(int i = 1; i <= 11; i++){ write(sprintf("%d",i)); if(i == 10){ break; } write(", "); } write("\n");
}</lang>
The most idiomatic way of inserting delimiters in Pike is the multiplication operator and it's symmetry with division of strings. <lang>> "1, 2, 3"/", "; Result: ({ "1", "2", "3" }) > ({ "1", "2", "3" })*", "; Result: "1, 2, 3"</lang>
So achieving the result of this task with the method more suited to Pike would be: <lang>array a = (array(string))enumerate(10, 1, 1); write(a * ", " + "\n");</lang>
PL/I
<lang PL/I> do i = 1 to 10;
put edit (trim(i)) (a); if i < 10 then put edit (', ') (a);
end; </lang>
Plain English
<lang plainenglish>To run: Start up. Write the numbers up to 10 on the console. Wait for the escape key. Shut down.
To write the numbers up to a number on the console: If a counter is past the number, exit. Convert the counter to a string. Write the string on the console without advancing. If the counter is less than the number, write ", " on the console without advancing. Repeat.</lang>
Pop11
<lang pop11>lvars i; for i from 1 to 10 do
printf(i, '%p'); quitif(i = 10); printf(', ', '%p');
endfor; printf('\n', '%p');</lang>
PowerShell
<lang powershell>for ($i = 1; $i -le 10; $i++) {
Write-Host -NoNewLine $i if ($i -eq 10) { Write-Host break } Write-Host -NoNewLine ", "
}</lang>
An interesting alternative solution, although not strictly a loop, even though switch
certainly loops over the given range.
<lang powershell>switch (1..10) {
{ $true } { Write-Host -NoNewLine $_ } { $_ -lt 10 } { Write-Host -NoNewLine ", " } { $_ -eq 10 } { Write-Host }
}</lang>
Prolog
<lang prolog>example :-
between(1,10,Val), write(Val), Val<10, write(', '), fail.
example.</lang>
?- example. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 true.
PureBasic
<lang PureBasic>x=1 Repeat
Print(Str(x)) x+1 If x>10: Break: EndIf Print(", ")
ForEver</lang>
Python
The particular pattern and example chosen in the task description is recognised by the Python language and there are more idiomatic ways to achieve the result that don't even require an explicit conditional test such as: <lang python>print ( ', '.join(str(i+1) for i in range(10)) )</lang> But the named pattern is shown by code such as the following: <lang python>>>> from sys import stdout >>> write = stdout.write >>> n, i = 10, 1 >>> while True:
write(i) i += 1 if i > n: break write(', ')
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
>>></lang>
List comprehension one-liner <lang python> [print(str(i+1) + ", ",end=) if i < 9 else print(i+1) for i in range(10)] </lang>
Quackery
<lang Quackery> 10 times
[ i^ 1+ echo i 0 = iff conclude done say ", " ]</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
R
The natural way to solve this task in R is: <lang R>paste(1:10, collapse=", ")</lang> The task specifies that we should use a loop however, so this more verbose code is needed. <lang R>for(i in 1:10) {
cat(i) if(i==10) { cat("\n") break } cat(", ")
}</lang>
Racket
<lang Racket>#lang racket (for ((i (in-range 1 15)))
(display i) #:break (= 10 i) (display ", "))</lang>
Gives the desired output.
Raku
(formerly Perl 6) <lang perl6>for 1 .. 10 {
.print; last when 10; print ', ';
}
print "\n";</lang>
REBOL
<lang REBOL>REBOL [
Title: "Loop Plus Half" URL: http://rosettacode.org/wiki/Loop/n_plus_one_half
]
repeat i 10 [ prin i if 10 = i [break] prin ", " ] print ""</lang>
Red
<lang rebol>Red[]
repeat i 10 [
prin i if 10 = i [break] prin ", "
] print ""</lang>
Relation
<lang Relation> set i = 1 set result = "" while i <= 10 set result = result . i if i < 10 set result = result . ", " end if set i = i + 1 end while echo result </lang>
REXX
two CHAROUTs
<lang rexx>/*REXX program displays: 1,2,3,4,5,6,7,8,9,10 */
do j=1 to 10 call charout ,j /*write the DO loop index (no LF). */ if j<10 then call charout ,"," /*append a comma for one-digit numbers.*/ end /*j*/ /*stick a fork in it, we're all done. */</lang>
output
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
one CHAROUT
<lang rexx>/*REXX program displays: 1,2,3,4,5,6,7,8,9,10 */
do j=1 for 10 /*using FOR is faster than TO. */ call charout ,j || left(',',j<10) /*display J, maybe append a comma (,).*/ end /*j*/ /*stick a fork in it, we're all done. */</lang>
output
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
version 3 if the number of items is not known
<lang rexx>list='aa bb cc dd' sep=', ' Do i=1 By 1 While list<>
If i>1 Then Call charout ,sep Parse Var list item list Call charout ,item End</lang>
- Output:
aa, bb, cc, dd
Ring
<lang ring> for x = 1 to 10 see x if x=10 exit ok see ", " next see nl </lang>
Ruby
<lang ruby> (1..10).each do |i|
print i break if i == 10 print ", "
end puts</lang> More idiomatic Ruby to obtain the same result is: <lang ruby> puts (1..10).join(", ")</lang>
Run BASIC
<lang runbasic> FOR i = 1 TO 10
PRINT cma$;i; cma$ = " , "
NEXT i </lang>
Rust
<lang rust>fn main() {
for i in 1..=10 { print!("{}{}", i, if i < 10 { ", " } else { "\n" }); }
}</lang>
More like the problem description: <lang rust>fn main() {
for i in 1..=10 { print!("{}", i); if i == 10 { break; } print!(", "); } println!();
}</lang>
Alternative solution using join. <lang rust>fn main() {
println!( "{}", (1..=10) .map(|i| i.to_string()) .collect::<Vec<_>>() .join(", ") );
}</lang>
S-lang
This may constitute not following directions, but I've always felt the most readable and general way to code this is to move the "optional" part from the bottom to the top of the loop, then NOT include it on the FIRST pass: <lang S-lang>variable more = 0, i; foreach i ([1:10]) {
if (more) () = printf(", "); printf("%d", i); more = 1;
}</lang>
Salmon
<lang Salmon>iterate (x; [1...10])
{ print(x); if (x == 10) break;; print(", "); };
print("\n");</lang>
Scala
<lang Scala>var i = 1 while ({
print(i) i < 10
}) {
print(", ") i += 1
} println()</lang> <lang Scala>println((1 to 10).mkString(", "))</lang>
Scheme
It is possible to use continuations: <lang scheme>(call-with-current-continuation
(lambda (esc) (do ((i 1 (+ 1 i))) (#f) (display i) (if (= i 10) (esc (newline))) (display ", "))))</lang>
But usually making the tail recursion explicit is enough: <lang scheme>(let loop ((i 0))
(display i) (if (= i 10) (newline) (begin (display ", ") (loop (+ 1 i)))))</lang>
Scilab
<lang>for i=1:10
printf("%2d ",i) if i<10 then printf(", "); end
end printf("\n")</lang>
- Output:
1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10
Seed7
<lang seed7>$ include "seed7_05.s7i";
const proc: main is func
local var integer: number is 0; begin for number range 1 to 10 do write(number); if number < 10 then write(", ") end if; end for; writeln; end func;</lang>
Sidef
<lang ruby>for (1..10) { |i|
print i; i == 10 && break; print ', ';
}
print "\n";</lang>
Smalltalk
<lang smalltalk>1 to: 10 do: [:n |
Transcript show: n asString. n < 10 ifTrue: [ Transcript show: ', ' ]
]</lang> Smalltalk/X and Pharo/Squeak have special enumeration messages for this in their Collection class, which executes another action in-between iterated elements:
<lang smalltalk>(1 to: 10) do: [:n |
Transcript show: n asString.
] separatedBy:[
Transcript show: ', '
]</lang> That is a bit different from the task's specification, but does what is needed here, and is more general in working with any collection (in the above case: a range aka "Interval"). It does not depend on the collection being addressed by an integer index and/or keeping a count inside the loop.
SNOBOL4
It's idiomatic in Snobol to accumulate the result in a string buffer for line output, and to use the same statement for loop control and the comma.
<lang SNOBOL4>loop str = str lt(i,10) (i = i + 1) :f(out)
str = str ne(i,10) ',' :s(loop)
out output = str end</lang>
For the task description, it's possible (implementation dependent) to set an output variable to raw mode for character output within the loop.
This example also breaks the loop explicitly: <lang SNOBOL4> output('out',1,'-[-r1]') loop i = lt(i,10) i + 1 :f(end)
out = i eq(i,10) :s(end) out = ',' :(loop)
end</lang>
- Output:
1,2,3,4,5,6,7,8,9,10
SNUSP
<lang snusp>@\>@\>@\>+++++++++<!/+. >-?\# digit and loop test
| | \@@@+@+++++# \>>.<.<</ comma and space | \@@+@@+++++# \@@@@=++++#</lang>
Spin
<lang spin>con
_clkmode = xtal1 + pll16x _clkfreq = 80_000_000
obj
ser : "FullDuplexSerial.spin"
pub main | n
ser.start(31, 30, 0, 115200)
repeat n from 1 to 10 ser.dec(n) if n<10 ser.str(string(", ")) ser.str(string(13, 10))
waitcnt(_clkfreq + cnt) ser.stop cogstop(0)</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Stata
<lang stata>forv i=1/10 { di `i' _continue if `i'<10 { di ", " _continue } else { di } }</lang>
Mata
<lang stata>mata for (i=1; i<=10; i++) { printf("%f",i) if (i<10) { printf(", ") } else { printf("\n") } } end</lang>
Swift
<lang swift>for var i = 1; ; i++ {
print(i) if i == 10 { println() break } print(", ")
}</lang>
The usual way to do this with Swift 2 is:
<lang swift> for i in 1...10 {
print(i, terminator: i == 10 ? "\n" : ", ")
} </lang> To satisfy the specification, we have to do something similar to Swift 1.x and other C-like languages: <lang swift>for var i = 1; ; i++ {
print(i, terminator: "") if i == 10 { print("") break } print(", ", terminator: "")
}</lang>
Tcl
<lang tcl>for {set i 1; set end 10} true {incr i} {
puts -nonewline $i if {$i >= $end} break puts -nonewline ", "
} puts ""</lang> However, that's not how the specific task (printing 1..10 with comma separators) would normally be done. (Note, the solution below is not a solution to the half-looping problem.) <lang tcl>proc range {from to} {
set result {} for {set i $from} {$i <= $to} {incr i} { lappend result $i } return $i
}
puts [join [range 1 10] ", "] ;# ==> 1, 2, 3, 4, 5, 6, 7, 8, 9, 10</lang>
TI-89 BASIC
There is no horizontal cursor position on the program IO screen, so we concatenate strings instead.
<lang ti89b>Local str "" → str For i,1,10
str & string(i) → str If i < 10 Then str & "," → str EndIf
EndFor Disp str</lang>
Tiny BASIC
Tiny BASIC does not support string concatenation so each number is on a separate line but this is at least in the spirit of the task description. <lang tinybasic> LET I = 1
10 IF I = 10 THEN PRINT I IF I < 10 THEN PRINT I,", " IF I = 10 THEN END LET I = I + 1 GOTO 10</lang>
TUSCRIPT
<lang tuscript> $$ MODE TUSCRIPT line="" LOOP n=1,10
line=CONCAT (line,n) IF (n!=10) line=CONCAT (line,", ")
ENDLOOP PRINT line </lang> Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
UNIX Shell
<lang bash>for(( Z=1; Z<=10; Z++ )); do
echo -e "$Z\c" if (( Z != 10 )); then echo -e ", \c" fi
done</lang>
<lang bash>for ((i=1;i<=$((last=10));i++)); do
echo -n $i [ $i -eq $last ] && break echo -n ", "
done</lang>
UnixPipes
The last iteration is handled automatically for us when there is no element in one of the pipes. <lang bash>yes \ | cat -n | head -n 10 | paste -d\ - <(yes , | head -n 9) | xargs echo</lang>
Ursa
<lang ursa>decl int i for (set i 1) (< i 11) (inc i)
out i console if (= i 10) break end if out ", " console
end for out endl console</lang>
V
<lang v>[loop
[ [10 =] [puts] [true] [dup put ',' put succ loop] ] when].</lang>
Using it
|1 loop =1,2,3,4,5,6,7,8,9,10
Vala
<lang vala>void main() {
for (int i = 1; i <= 10; i++) { stdout.printf("%d", i); stdout.printf(i == 10 ? "\n" : ", "); }
}</lang>
VBA
<lang VB>Public Sub WriteACommaSeparatedList()
Dim i As Integer Dim a(1 To 10) As String For i = 1 To 10 a(i) = CStr(i) Next i Debug.Print Join(a, ", ")
End Sub</lang>
Vedit macro language
This example writes the output into current edit buffer. <lang vedit>for (#1 = 1; 1; #1++) {
Num_Ins(#1, LEFT+NOCR) if (#1 == 10) { Break } Ins_Text(", ")
} Ins_Newline</lang>
Vim Script
<lang vim>for i in range(1, 10)
echon i if (i != 10) echon ", " endif
endfor</lang>
Visual Basic .NET
<lang vbnet>For i = 1 To 10
Console.Write(i) If i = 10 Then Exit For Console.Write(", ")
Next</lang>
Vlang
<lang go>fn main() {
for i := 1; ; i++ { print(i) if i == 10 { break } print(", ") }
}</lang>
Wart
<lang wart>for i 1 (i <= 10) ++i
pr i if (i < 10) pr ", "
(prn)</lang>
Wee Basic
print 1 "" ensures the end of program text is separate from the list of numbers. <lang Wee Basic>print 1 "" for numbers=1 to 10 print 1 at numbers*3-2,0 numbers if numbers<>10 print 1 at numbers*3-1,0 "," endif end</lang>
Wren
<lang ecmascript>for (i in 1..10) {
System.write(i) System.write((i < 10) ? ", " : "\n")
}</lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
XBasic
<lang xbasic> PROGRAM "n_plus_one_half"
DECLARE FUNCTION Entry()
FUNCTION Entry()
FOR i% = 1 TO 10 PRINT i%; IF i% = 10 THEN EXIT FOR PRINT ","; NEXT i% PRINT ' If equality checking affected the efficiency ' or if the last value were treated in different manner, ' one would extract the last iteration: FOR i% = 1 TO 9 PRINT i%; ","; NEXT i% PRINT 10
END FUNCTION END PROGRAM </lang>
- Output:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
XPL0
<lang XPL0>codes CrLf=9, IntOut=11, Text=12; int N; [for N:= 1 to 10 do \best way to do this
[IntOut(0, N); if N#10 then Text(0, ", ")];
CrLf(0);
N:= 1; \way suggested by task statement loop [IntOut(0, N);
if N=10 then quit; Text(0, ", "); N:= N+1; ];
CrLf(0); ]</lang>
Yabasic
<lang Yabasic>for i = 1 to 10
print i; if i < 10 then print ", "; : endif
next i print
end</lang>
zkl
<lang zkl>foreach n in ([1..10]){ print(n); if (n!=10) print(",") }</lang> Or, using a state machine: <lang zkl>[1..10].pump(Console.print, Void.Drop, T(Void.Write,",",Void.Drop));</lang> where pump is (sink, action, action ...). The first Drop writes the first object from the source (1) to the sink and drops out (and that iteration of the loop is done). For the rest of the loop, Write collects things to write to the sink: a comma and the number, eg ",2". Or: <lang zkl>[1..10].pump(Console.print, Void.Drop, fcn(n){ String(",",n) });</lang>
Zig
<lang zig>const std = @import("std"); pub fn main() !void {
const stdout_wr = std.io.getStdOut().writer(); var i: u8 = 1; while (i <= 10) : (i += 1) { try stdout_wr.print("{d}", .{i}); if (i == 10) { try stdout_wr.writeAll("\n"); } else { try stdout_wr.writeAll(", "); } }
}</lang>