Increment a numerical string
Increment a numerical string.
You are encouraged to solve this task according to the task description, using any language you may know.
- Task
11l
<lang 11l>V next = String(Int(‘123’) + 1)</lang>
8080 Assembly
<lang 8080asm> org 100h jmp demo ;;; Increment the number in the $-terminated string under HL. ;;; The new string is written back to the original location. ;;; It may grow by one byte (e.g. 999 -> 1000). incstr: mvi a,'$' ; End marker lxi d,303Ah ; D='0', E='9'+1 lxi b,0 ; Find the end of the string and find the length isrch: cmp m ; Are we there yet? inx b ; If not, try next character inx h jnz isrch dcx h dcx b mov a,b ; Is the string empty? ora c rz ; Then return (do nothing) inx b idigit: dcx b ; Go to previous digit dcx h mov a,b ; Are we at the beginning of the string? ora c jz igrow ; Then the string grows (999 -> 1000) inr m ; Otherwise, increment the digit mov a,e cmp m ; Did we try to increment '9'? rnz ; If not, we're done, return mov m,d ; But if so, this digit is now a 0 jmp idigit ; And we should do the next digit igrow: inx h mvi m,'1' ; The string should now be '10000...' inx h ; We know the string is at least one char long mvi a,'$' izero: cmp m ; Are we at the end yet? mov m,d ; In any case, write a zero inx h jnz izero ; If not done, write a zero mov m,a ; Finally, reterminate the string ret ;;; Demo code: increment the CP/M command line argument demo: lxi h,80h ; $-terminate the string mov a,m adi 81h ; Length is at 80h, the argument itself at 81h mov l,a mvi m,'$' mvi l,80h ; Skip any spaces mvi a,' ' space: inx h cmp m jz space push h ; Store the beginning of the string call incstr ; Increment the number in the string pop d ; Print the string mvi c,9 jmp 5</lang>
8086 Assembly
<lang asm> cpu 8086 bits 16 section .text org 100h jmp demo ; Jump towards demo code ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Increment the number in the $-terminated string ;;; in [ES:DI]. The string is written back to its original ;;; location. It may grow by one byte. incnum: mov al,'$' ; Find string terminator mov bx,di ; Store the beginning of the string mov cx,-1 repne scasb dec di ; Move to the terminator cmp bx,di ; If the string is empty, do nothing je .out .digit: cmp bx,di ; Is this the first digit? je .grow ; If so, the string grows dec di ; Go one digit backwards inc byte [es:di] ; Increment the digit cmp byte [es:di],'9'+1 ; Did we increment past 9? jne .out ; If not, we're done mov byte [es:di],'0' ; Otherwise, write a zero jmp .digit ; And increment the next digit .grow: mov al,'1' ; Write an 1 first (we know the string stosb ; is at least one character long) dec al ; Zero .zero: cmp byte [es:di],'$' ; Are we about to overwrite stosb ; the terminator? First, do it anyway; jne .zero ; Keep writing zeroes until $ is reached mov al,'$' ; Finally, write a new terminator stosb .out: ret ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Demo code: increment the number on the MS-DOS ;;; command line. demo: mov si,80h ; $-terminate the string lodsb xor bh,bh mov bl,al mov byte [si+bx],'$' mov al,' ' ; Skip past any spaces mov cx,-1 mov di,si repe scasb dec di mov dx,di ; Keep start of string in DX call incnum ; Increment the number in the string mov ah,9 ; Print the string int 21h ret</lang>
AArch64 Assembly
<lang AArch64 Assembly> /* ARM assembly AARCH64 Raspberry PI 3B */ /* program incstring64.s */
/*******************************************/ /* Constantes file */ /*******************************************/ /* for this file see task include a file in language AArch64 assembly*/ .include "../includeConstantesARM64.inc"
.equ BUFFERSIZE, 100 /*******************************************/ /* Initialized data */ /*******************************************/ .data szMessNum: .asciz "Enter number : \n" szCarriageReturn: .asciz "\n" szMessResult: .asciz "Increment number is = @ \n" // message result
/*******************************************/ /* UnInitialized data */ /*******************************************/ .bss sBuffer: .skip BUFFERSIZE sZoneConv: .skip 24 /*******************************************/ /* code section */ /*******************************************/ .text .global main main: // entry of program
ldr x0,qAdrszMessNum
bl affichageMess
mov x0,#STDIN // Linux input console
ldr x1,qAdrsBuffer // buffer address
mov x2,#BUFFERSIZE // buffer size
mov x8, #READ // request to read datas
svc 0 // call system
ldr x1,qAdrsBuffer // buffer address
strb wzr,[x1,x0] // store zero at the end of input string (x0
//
ldr x0,qAdrsBuffer // buffer address
bl conversionAtoD // conversion string in number in x0
// increment x0
add x0,x0,1
// conversion register to string
ldr x1,qAdrsZoneConv
bl conversion10S // call conversion
ldr x0,qAdrszMessResult
ldr x1,qAdrsZoneConv
bl strInsertAtCharInc // insert result at @ character
bl affichageMess // display message
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 qAdrszMessNum: .quad szMessNum qAdrsBuffer: .quad sBuffer qAdrszMessResult: .quad szMessResult qAdrszCarriageReturn: .quad szCarriageReturn /********************************************************/ /* File Include fonctions */ /********************************************************/ /* for this file see task include a file in language AArch64 assembly */ .include "../includeARM64.inc" </lang>
- Output:
Enter number : 50 Increment number is = +51 pi@debian-buster-64:~/asm64/rosetta/asm4 $ incstring64 Enter number : -12 Increment number is = -11
ABAP
<lang ABAP>report zz_incstring perform test using: '0', '1', '-1', '10000000', '-10000000'.
form test using iv_string type string.
data: lv_int type i,
lv_string type string.
lv_int = iv_string + 1.
lv_string = lv_int.
concatenate '"' iv_string '" + 1 = "' lv_string '"' into lv_string.
write / lv_string.
endform. </lang>
- Output:
"0" + 1 = "1 " "1" + 1 = "2 " "-1" + 1 = "0 " "10000000" + 1 = "10000001 " "-10000000" + 1 = "9999999-"
Action!
<lang Action!>PROC Increment(CHAR ARRAY src,dst)
INT val
val=ValI(src) val==+1 StrI(val,dst)
RETURN
PROC Test(CHAR ARRAY src)
CHAR ARRAY dst(10)
Increment(src,dst)
PrintF("%S+1=%S%E",src,dst)
RETURN
PROC Main()
Test("0")
Test("1")
Test("9999")
Test("-1")
Test("-2")
Test("-10000")
RETURN</lang>
- Output:
Screenshot from Atari 8-bit computer
0+1=1 1+1=2 9999+1=10000 -1+1=0 -2+1=-1 -10000+1=-9999
ActionScript
<lang ActionScript>function incrementString(str:String):String { return String(Number(str)+1); }</lang>
Ada
The standard Ada package Ada.Strings.Fixed provides a function for trimming blanks from a string. <lang ada>S : String := "12345"; S := Ada.Strings.Fixed.Trim(Source => Integer'Image(Integer'Value(S) + 1), Side => Ada.Strings.Both);</lang>
Aime
<lang aime> o_text(itoa(atoi("2047") + 1)); o_byte('\n'); </lang>
ALGOL 68
<lang algol68>STRING s := "12345"; FILE f; INT i; associate(f, s); get(f,i); i+:=1; s:=""; reset(f); put(f,i); print((s, new line))</lang>
- Output:
+12346
ALGOL W
Increments a string representaton of an integer, without converting it to an integer and so allows values greater than will fit into an Algol W integer (which is restricted to 32 bits). <lang algolw>begin
% returns a string representing the number in s incremented %
% As strings are fixed length, the significant length of s must %
% be specified in length %
% s must contain an unsigned integer %
% If the string is invalid or the result would require more %
% than 256 characters (the maximum string length), "error" %
% is returned %
string(256) procedure increment( string(256) value s
; integer value length
) ;
begin
logical isValid;
integer rPos, sPos, carry;
string(256) iValue;
string(1) c;
isValid := true;
iValue := " ";
rPos := 256;
sPos := length - 1;
carry := 1; % ensure the first digit is incremented %
while isValid and sPos >= 0 and rPos >= 0 do begin
c := s( sPos // 1 );
sPos := sPos - 1;
if c not = " " then begin
isValid := ( c >= "0" and c <= "9" );
if isValid then begin
integer d;
d := ( decode( c ) - decode( "0" ) ) + carry;
carry := d div 10;
rPos := rPos - 1;
iValue( rPos // 1 ) := code( decode( "0" ) + d rem 10 )
end if_isValid
end if_c_ne_space
end while_isValid_and_sPos_ge_0_and_rPOs_ge_0 ;
if isValid then begin
% the number was incremented successfully %
if carry not = 0 then begin
% need an extra digit %
if rPos <= 0
then isValid := false % no room for an extra digit %
else begin
% have space for an extra digit %
rPos := rPos - 1;
iValue( rPos // 1 ) := code( decode( "0" ) + carry )
end if_rPos_lt_0__
end if_carry_gt_0
end if_isValid ;
if not isValid then begin
% s is not a numeric string or the result would be longer than 256 characters %
iValue := "error"
end
else begin
% the string could be incremented %
string(256) rightJustifiedValue;
rightJustifiedValue := iValue;
iValue := " ";
for iPos := 0 until 255 - rPos do iValue( iPos // 1 ) := rightJustifiedValue( rPos + iPos // 1 )
end if_not_isValid_or_carry_ne_0__ ;
iValue
end increment ;
% writes the string s, up to the first blank %
procedure writeonToBlank ( string(256) value s ) ;
begin
integer sPos;
sPos := 0;
while sPos < 256 and s( sPos // 1 ) not = " " do begin
writeon( s_w := 0, s( sPos // 1 ) );
sPos := sPos + 1
end while_spos_lt_256_and_s_Spos_ne_space
end writeonToBlank ;
% test increment %
write( " 0 + 1: " ); writeonToBlank( increment( "0", 1 ) );
write( " 9 + 1: " ); writeonToBlank( increment( "9", 1 ) );
write( " 123456789 + 1: " ); writeonToBlank( increment( "123456789", 9 ) );
write( "99999999999999999999 + 1: " ); writeonToBlank( increment( "99999999999999999999", 20 ) )
end.</lang>
- Output:
0 + 1: 1
9 + 1: 10
123456789 + 1: 123456790
99999999999999999999 + 1: 100000000000000000000
Apex
<lang apex> string count = '12345'; count = String.valueOf(integer.valueOf(count)+1); system.debug('Incremental Value : '+count); </lang>
- Output:
12346
APL
<lang apl>⍕1+⍎'12345'</lang>
- Output:
12346
AppleScript
Preserving the distinction between real and integer strings, and allowing for strings containing non-numeric tokens and/or multiple numeric expressions. Provides an option to either retain or prune out any non-numeric tokens in the string:
<lang applescript>use AppleScript version "2.4" use framework "Foundation" use scripting additions
-- succString :: Bool -> String -> String on succString(blnPruned, s)
script go
on |λ|(w)
try
if w contains "." then
set v to w as real
else
set v to w as integer
end if
{(1 + v) as string}
on error
if blnPruned then
{}
else
{w}
end if
end try
end |λ|
end script
unwords(concatMap(go, |words|(s)))
end succString
-- TEST ---------------------------------------------------
on run
script test
on |λ|(bln)
succString(bln, ¬
"41 pine martens in 1491.3 -1.5 mushrooms ≠ 136")
end |λ|
end script
unlines(map(test, {true, false}))
end run
--> 42 1492.3 -0.5 137 --> 42 pine martens in 1492.3 -0.5 mushrooms ≠ 137
-- GENERIC ------------------------------------------------
-- concatMap :: (a -> [b]) -> [a] -> [b] on concatMap(f, xs)
set lng to length of xs
set acc to {}
tell mReturn(f)
repeat with i from 1 to lng
set acc to acc & |λ|(item i of xs, i, xs)
end repeat
end tell
return acc
end concatMap
-- map :: (a -> b) -> [a] -> [b] on map(f, xs)
tell mReturn(f)
set lng to length of xs
set lst to {}
repeat with i from 1 to lng
set end of lst to |λ|(item i of xs, i, xs)
end repeat
return lst
end tell
end map
-- Lift 2nd class handler function into 1st class script wrapper -- mReturn :: First-class m => (a -> b) -> m (a -> b) on mReturn(f)
if class of f is script then
f
else
script
property |λ| : f
end script
end if
end mReturn
-- unlines :: [String] -> String on unlines(xs)
set {dlm, my text item delimiters} to ¬
{my text item delimiters, linefeed}
set str to xs as text
set my text item delimiters to dlm
str
end unlines
-- unwords :: [String] -> String on unwords(xs)
set {dlm, my text item delimiters} to ¬
{my text item delimiters, space}
set s to xs as text
set my text item delimiters to dlm
return s
end unwords
-- words :: String -> [String] on |words|(s)
set ca to current application
(((ca's NSString's stringWithString:(s))'s ¬
componentsSeparatedByCharactersInSet:(ca's ¬
NSCharacterSet's whitespaceAndNewlineCharacterSet()))'s ¬
filteredArrayUsingPredicate:(ca's ¬
NSPredicate's predicateWithFormat:"0 < length")) as list
end |words|</lang>
- Output:
42 1492.3 -0.5 137 42 pine martens in 1492.3 -0.5 mushrooms ≠ 137
ARM Assembly
<lang ARM Assembly>
/* ARM assembly Raspberry PI */ /* program incstring.s */
/* Constantes */ .equ BUFFERSIZE, 100 .equ STDIN, 0 @ Linux input console .equ STDOUT, 1 @ Linux output console .equ EXIT, 1 @ Linux syscall .equ READ, 3 @ Linux syscall .equ WRITE, 4 @ Linux syscall /* Initialized data */ .data szMessNum: .asciz "Enter number : \n" szCarriageReturn: .asciz "\n" szMessResult: .ascii "Increment number is = " @ message result sMessValeur: .fill 12, 1, ' '
.asciz "\n"
/* UnInitialized data */ .bss sBuffer: .skip BUFFERSIZE
/* code section */ .text .global main main: /* entry of program */
push {fp,lr} /* saves 2 registers */
ldr r0,iAdrszMessNum bl affichageMess mov r0,#STDIN @ Linux input console ldr r1,iAdrsBuffer @ buffer address mov r2,#BUFFERSIZE @ buffer size mov r7, #READ @ request to read datas swi 0 @ call system ldr r1,iAdrsBuffer @ buffer address mov r2,#0 @ end of string strb r2,[r1,r0] @ store byte at the end of input string (r0 @ ldr r0,iAdrsBuffer @ buffer address bl conversionAtoD @ conversion string in number in r0 @ increment r0 add r0,#1 @ conversion register to string ldr r1,iAdrsMessValeur bl conversion10S @ call conversion ldr r0,iAdrszMessResult bl affichageMess @ display message
100: /* standard end of the program */
mov r0, #0 @ return code
pop {fp,lr} @restaur 2 registers
mov r7, #EXIT @ request to exit program
swi 0 @ perform the system call
iAdrsMessValeur: .int sMessValeur iAdrszMessNum: .int szMessNum iAdrsBuffer: .int sBuffer iAdrszMessResult: .int szMessResult iAdrszCarriageReturn: .int szCarriageReturn /******************************************************************/ /* display text with size calculation */ /******************************************************************/ /* r0 contains the address of the message */ affichageMess:
push {fp,lr} /* save registres */
push {r0,r1,r2,r7} /* save others registers */
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" */
swi #0 /* call systeme */
pop {r0,r1,r2,r7} /* restaur others registers */
pop {fp,lr} /* restaur des 2 registres */
bx lr /* return */
/******************************************************************/
/* Convert a string to a number stored in a registry */ /******************************************************************/ /* r0 contains the address of the area terminated by 0 or 0A */ /* r0 returns a number */ conversionAtoD:
push {fp,lr} @ save 2 registers
push {r1-r7} @ save others registers
mov r1,#0
mov r2,#10 @ factor
mov r3,#0 @ counter
mov r4,r0 @ save address string -> r4
mov r6,#0 @ positive sign by default
mov r0,#0 @ initialization to 0
1: /* early space elimination loop */
ldrb r5,[r4,r3] @ loading in r5 of the byte located at the beginning + the position cmp r5,#0 @ end of string -> end routine beq 100f cmp r5,#0x0A @ end of string -> end routine beq 100f cmp r5,#' ' @ space ? addeq r3,r3,#1 @ yes we loop by moving one byte beq 1b cmp r5,#'-' @ first character is - moveq r6,#1 @ 1 -> r6 beq 3f @ then move on to the next position
2: /* beginning of digit processing loop */
cmp r5,#'0' @ character is not a number blt 3f cmp r5,#'9' @ character is not a number bgt 3f /* character is a number */ sub r5,#48 umull r0,r1,r2,r0 @ multiply par factor 10
cmp r1,#0 @ overflow ?
bgt 99f @ overflow error add r0,r5 @ add to r0
3:
add r3,r3,#1 @ advance to the next position ldrb r5,[r4,r3] @ load byte cmp r5,#0 @ end of string -> end routine beq 4f cmp r5,#0x0A @ end of string -> end routine beq 4f b 2b @ loop
4:
cmp r6,#1 @ test r6 for sign moveq r1,#-1 muleq r0,r1,r0 @ if negatif, multiply par -1 b 100f
99: /* overflow error */
ldr r0,=szMessErrDep bl affichageMess mov r0,#0 @ return zero if error
100:
pop {r1-r7} @ restaur other registers
pop {fp,lr} @ restaur 2 registers
bx lr @return procedure
/* constante program */ szMessErrDep: .asciz "Too large: overflow 32 bits.\n" .align 4
/***************************************************/ /* Converting a register to a signed decimal */ /***************************************************/ /* r0 contains value and r1 area address */ conversion10S:
push {r0-r4,lr} @ save registers
mov r2,r1 /* debut zone stockage */
mov r3,#'+' /* par defaut le signe est + */
cmp r0,#0 @ negative number ?
movlt r3,#'-' @ yes
mvnlt r0,r0 @ number inversion
addlt r0,#1
mov r4,#10 @ length area
1: @ start loop
bl divisionpar10 add r1,#48 @ digit strb r1,[r2,r4] @ store digit on area sub r4,r4,#1 @ previous position cmp r0,#0 @ stop if quotient = 0 bne 1b
strb r3,[r2,r4] @ store signe subs r4,r4,#1 @ previous position blt 100f @ if r4 < 0 -> end
mov r1,#' ' @ space
2:
strb r1,[r2,r4] @store byte space subs r4,r4,#1 @ previous position bge 2b @ loop if r4 > 0
100:
pop {r0-r4,lr} @ restaur registers
bx lr
/***************************************************/
/* 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
ldr r3, .Ls_magic_number_10 /* r1 <- magic_number */
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 /* leave function */
.align 4
.Ls_magic_number_10: .word 0x66666667
</lang>
Arturo
<lang rebol>num: "12349"
print ["The next number is:" (to :integer num)+1]</lang>
- Output:
The next number is: 12350
Asymptote
<lang Asymptote>string cadena = "12345.78"; cadena = string((real)cadena + 1); write(cadena);</lang>
- Output:
12346.78
AutoHotkey
<lang autohotkey>str = 12345 MsgBox % str += 1</lang>
- Output:
12346
AutoIt
<lang autoIt>Global $x = "12345" $x += 1 MsgBox(0,"",$x)</lang>
- Output:
12346
Avail
<lang Avail>numberString ::= "1080"; incremented ::= numberString (base 10) + 1;</lang>
AWK
The example shows that the string s can be incremented, but after that still is a string of length 2. <lang awk>$ awk 'BEGIN{s="42"; s++; print s"("length(s)")" }' 43(2)</lang>
BASIC
<lang qbasic>s$ = "12345" s$ = STR$(VAL(s$) + 1)</lang>
BASIC256
<lang freebasic>cadena$ = "12345" cadena$ = string(val(cadena$) + 1)
- or also
cadena$ = string(FromRadix(cadena$,10) + 1)</lang>
OxygenBasic
When a number is assigned to a string, it autoconverts. <lang> string s="122" s=val(s)+1 print s 'result: "123" </lang>
True BASIC
<lang qbasic>LET cadena$ = "12345" LET cadena$ = STR$(VAL(cadena$) + 1) PRINT cadena$ END</lang>
Yabasic
<lang yabasic>cadena$ = "12345" cadena$ = str$(val(cadena$) + 1)</lang>
IS-BASIC
<lang IS-BASIC>100 LET S$="12345" 110 LET S$=STR$(VAL(S$)+1)</lang>
ZX Spectrum Basic
The ZX Spectrum needs line numbers and a let statement, but the same technique can be used:
<lang zxbasic>10 LET s$ = "12345" 20 LET s$ = STR$(VAL(s$) + 1)</lang>
Batch File
Since environment variables have no type distinction all numbers are simply numeric strings:
<lang dos>set s=12345 set /a s+=1</lang>
BBC BASIC
This assumes the task is about incrementing an arbitrary-length decimal string. <lang bbcbasic> num$ = "567"
REPEAT
PRINT num$
PROCinc$(num$)
UNTIL FALSE
END
DEF PROCinc$(RETURN n$)
LOCAL A$, I%
I% = LEN(n$)
REPEAT
A$ = CHR$(ASCMID$(n$,I%) + 1)
IF A$=":" A$ = "0"
MID$(n$,I%,1) = A$
I% -= 1
UNTIL A$<>"0" OR I%=0
IF A$="0" n$ = "1" + n$
ENDPROC</lang>
Boo
<lang boo>s = "1234" s = (int.Parse(s) + 1).ToString()</lang>
BQN
<lang BQN>1•Repr∘+•BQN "1234"</lang>
Bracmat
Numbers are strings. Bracmat supports rational numbers, including integers, using arbitrary-precision arithmetic. Pure imaginary numbers are formed using a factor i (or -i). There is no support for floating point arithmetics. (Historically, because the ARM 2 processor in the Archimedes computer didn't sport an FPU.)
<lang bracmat>(n=35664871829866234762187538073934873121878/6172839450617283945)
&!n+1:?n
&out$!n
35664871829866234762193710913385490405823/6172839450617283945
</lang>
Brat
<lang brat>#Convert to integer, increment, then back to string p ("100".to_i + 1).to_s #Prints 101</lang>
Burlesque
<lang burlesque> ri?ish </lang>
C
Handling strings of arbitrary sizes:<lang c>#include <stdio.h>
- include <string.h>
- include <stdlib.h>
/* Constraints: input is in the form of (\+|-)?[0-9]+
* and without leading zero (0 itself can be as "0" or "+0", but not "-0");
* input pointer is realloc'able and may change;
* if input has leading + sign, return may or may not keep it.
* The constranits conform to sprintf("%+d") and this function's own output.
*/
char * incr(char *s) { int i, begin, tail, len; int neg = (*s == '-'); char tgt = neg ? '0' : '9';
/* special case: "-1" */ if (!strcmp(s, "-1")) { s[0] = '0', s[1] = '\0'; return s; }
len = strlen(s); begin = (*s == '-' || *s == '+') ? 1 : 0;
/* find out how many digits need to be changed */ for (tail = len - 1; tail >= begin && s[tail] == tgt; tail--);
if (tail < begin && !neg) { /* special case: all 9s, string will grow */ if (!begin) s = realloc(s, len + 2); s[0] = '1'; for (i = 1; i <= len - begin; i++) s[i] = '0'; s[len + 1] = '\0'; } else if (tail == begin && neg && s[1] == '1') { /* special case: -1000..., so string will shrink */ for (i = 1; i < len - begin; i++) s[i] = '9'; s[len - 1] = '\0'; } else { /* normal case; change tail to all 0 or 9, change prev digit by 1*/ for (i = len - 1; i > tail; i--) s[i] = neg ? '9' : '0'; s[tail] += neg ? -1 : 1; }
return s; }
void string_test(const char *s) { char *ret = malloc(strlen(s)); strcpy(ret, s);
printf("text: %s\n", ret); printf(" ->: %s\n", ret = incr(ret)); free(ret); }
int main() { string_test("+0"); string_test("-1"); string_test("-41"); string_test("+41"); string_test("999"); string_test("+999"); string_test("109999999999999999999999999999999999999999"); string_test("-100000000000000000000000000000000000000000000");
return 0; }</lang>
- Output:
text: +0
->: +1text: -1
->: 0text: -41
->: -40text: +41
->: +42text: 999
->: 1000text: +999
->: 1000text: 109999999999999999999999999999999999999999
->: 110000000000000000000000000000000000000000text: -100000000000000000000000000000000000000000000
->: -99999999999999999999999999999999999999999999
C#
<lang csharp>string s = "12345"; s = (int.Parse(s) + 1).ToString(); // The above functions properly for strings >= Int32.MinValue and // < Int32.MaxValue. ( -2147483648 to 2147483646 )
// The following will work for any arbitrary-length integer string. // (Assuming that the string fits in memory, leaving enough space // for the temporary BigInteger created, plus the resulting string): using System.Numerics; string bis = "123456789012345678999999999"; bis = (BigInteger.Parse(bis) + 1).ToString(); // Note that extremely long strings will take a long time to parse // and convert from a BigInteger back into a string.</lang>
C++
<lang cpp>// standard C++ string stream operators
- include <cstdlib>
- include <string>
- include <sstream>
// inside a function or method... std::string s = "12345";
int i; std::istringstream(s) >> i; i++; //or: //int i = std::atoi(s.c_str()) + 1;
std::ostringstream oss; if (oss << i) s = oss.str();</lang>
<lang cpp>#include <string>
std::string s = "12345"; s = std::to_string(1+std::stoi(s));</lang>
<lang cpp>// Boost
- include <cstdlib>
- include <string>
- include <boost/lexical_cast.hpp>
// inside a function or method... std::string s = "12345"; int i = boost::lexical_cast<int>(s) + 1; s = boost::lexical_cast<std::string>(i);</lang>
<lang cpp>// Qt QString num1 = "12345"; QString num2 = QString("%1").arg(v1.toInt()+1);</lang>
<lang cpp>// MFC CString s = "12345"; int i = _ttoi(s) + 1; int i = _tcstoul(s, NULL, 10) + 1; s.Format("%d", i);</lang>
All of the above solutions only work for numbers <= INT_MAX. The following works for an (almost) arbitrary large number:
<lang cpp>#include <string>
- include <iostream>
- include <ostream>
void increment_numerical_string(std::string& s) {
std::string::reverse_iterator iter = s.rbegin(), end = s.rend();
int carry = 1;
while (carry && iter != end)
{
int value = (*iter - '0') + carry;
carry = (value / 10);
*iter = '0' + (value % 10);
++iter;
}
if (carry)
s.insert(0, "1");
}
int main() {
std::string big_number = "123456789012345678901234567899"; std::cout << "before increment: " << big_number << "\n"; increment_numerical_string(big_number); std::cout << "after increment: " << big_number << "\n";
}</lang>
Ceylon
<lang ceylon>shared void run() {
"Increments a numeric string by 1. Returns a float or integer depending on the string. Returns null if the string isn't a number." function inc(String string) => if(exists integer = parseInteger(string)) then integer + 1 else if(exists float = parseFloat(string)) then float + 1.0 else null;
value a = "1"; print(a); value b = inc(a); print(b); value c = "1.0"; print(c); value d = inc(c); print(d); }</lang>
Clojure
<lang lisp>(str (inc (Integer/parseInt "1234")))</lang>
CMake
CMake performs all arithmetic with numeric strings, through its math() command.
<lang cmake>set(string "1599") math(EXPR string "${string} + 1") message(STATUS "${string}")</lang>
-- 1600
COBOL
<lang cobol> PROGRAM-ID. increment-num-str.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 str PIC X(5) VALUE "12345".
01 num REDEFINES str PIC 9(5).
PROCEDURE DIVISION.
DISPLAY str
ADD 1 TO num
DISPLAY str
GOBACK
.</lang>
The following example also increments a numerical string, although it does not apear to. num-str is implicitly defined as USAGE DISPLAY which means its contents will be stored as characters. This means num-str is effectively a string of (numeric) characters.
<lang cobol> PROGRAM-ID. increment-num-str.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 num-str PIC 9(5) VALUE 12345.
PROCEDURE DIVISION.
DISPLAY num-str
ADD 1 TO num-str
DISPLAY num-str
GOBACK
.</lang>
Common Lisp
<lang lisp>(princ-to-string (1+ (parse-integer "1234")))</lang>
Component Pascal
BlackBox Component Builder <lang oberon2> MODULE Operations; IMPORT StdLog,Args,Strings;
PROCEDURE IncString(s: ARRAY OF CHAR): LONGINT; VAR resp: LONGINT; done: INTEGER; BEGIN Strings.StringToLInt(s,resp,done); INC(resp); RETURN resp END IncString;
PROCEDURE DoIncString*; VAR p: Args.Params; BEGIN Args.Get(p); IF p.argc > 0 THEN StdLog.String(p.args[0] + " + 1= ");StdLog.Int(IncString(p.args[0]));StdLog.Ln END END DoIncString;
END Operations.
</lang>
Execute: ^Q Operatiosn.DoIncString 124343~
- Output:
124343 + 1= 124344
D
<lang d>void main() {
import std.string;
immutable s = "12349".succ; assert(s == "12350");
}</lang>
Delphi
<lang Delphi>program IncrementNumericalString;
{$APPTYPE CONSOLE}
uses SysUtils;
const
STRING_VALUE = '12345';
begin
WriteLn(Format('"%s" + 1 = %d', [STRING_VALUE, StrToInt(STRING_VALUE) + 1]));
Readln;
end.</lang>
- Output:
"12345" + 1 = 123456
Dyalect
<lang dyalect>var str = "42" str = (parse(str) + 1).ToString()
//Another option: str = (Integer(str) + 1).ToString()
//And another option using interpolation: str = "\(parse(str) + 1)"
print(str) //Outputs 45</lang>
DWScript
<lang Delphi>var value : String = "1234"; value := IntToStr(StrToInt(value) + 1); PrintLn(value);</lang>
Déjà Vu
<lang dejavu> !. to-str ++ to-num "100"</lang>
- Output:
"101"
E
<lang e>__makeInt("1234", 10).next().toString(10)</lang>
EasyLang
<lang>a$ = "12" a$ = number a$ + 1 print a$</lang>
EchoLisp
<lang scheme> (number->string (1+ (string->number "665")))
→ "666"
</lang>
Eero
<lang objc>#import <Foundation/Foundation.h>
int main()
i := (int)'123' + 1 s := @(i).description
Log( '%@', s ) return 0</lang>
EGL
<lang EGL>s string = "12345"; s = 1 + s; // Note: s + 1 is a string concatenation.</lang>
Eiffel
<lang Eiffel> class APPLICATION
create make
feature {NONE}
make do io.put_string (increment_numerical_string ("7")) io.new_line io.put_string (increment_numerical_string ("99")) end
increment_numerical_string (s: STRING): STRING -- String 's' incremented by one. do Result := s.to_integer.plus (1).out end
end </lang> Output:
8 100
Elena
ELENA 4.x: <lang elena>import extensions;
public program() {
var s := "12345"; s := (s.toInt() + 1).toString(); console.printLine(s)
}</lang>
- Output:
12346
Elixir
Values can be converted to integers then converted back after incrementing <lang Elixir>increment1 = fn n -> to_string(String.to_integer(n) + 1) end
- Or piped
increment2 = fn n -> n |> String.to_integer |> +1 |> to_string end
increment1.("1") increment2.("100")</lang>
- Output:
"2" "101"
Case of char list:
<lang Elixir>iex(1)> (List.to_integer('12345') + 1) |> to_char_list
'12346'</lang>
Emacs Lisp
<lang lisp>(1+ (string-to-number "12345"))</lang>
Erlang
<lang erlang>integer_to_list(list_to_integer("1336")+1).</lang>
ERRE
<lang>
.................... s$="12345" s$=STR$(VAL(s$)+1) ....................
</lang>
Euphoria
<lang euphoria>include get.e
function val(sequence s)
sequence x x = value(s) return x[2]
end function
sequence s
s = "12345" s = sprintf("%d",{val(s)+1})</lang>
F#
<lang fsharp>let next = string( int( "1234" ) + 1 )</lang>
Factor
<lang factor>"1234" string>number 1 + number>string</lang>
Fantom
Within 'fansh':
<lang fantom> fansh> a := "123" 123 fansh> (a.toInt + 1).toStr 124 </lang>
Forth
This word causes the number whose string value is stored at the given location to be incremented. The address passed must contain enough space to hold the string representation of the new number. Error handling is rudimentary, and consists of aborting when the string does not contain a numerical value.
The word ">string" takes and integer and returns the string representation of that integer. I factored it out of the definitions below to keep the example simpler.
<lang forth>: >string ( d -- addr n )
dup >r dabs <# #s r> sign #> ;
- inc-string ( addr -- )
dup count number? not abort" invalid number" 1 s>d d+ >string rot place ;</lang>
Here is a version that can increment by any value
<lang forth>: inc-string ( addr n -- )
over count number? not abort" invalid number" rot s>d d+ >string rot place ;</lang>
Test the first version like this:
<lang forth>s" 123" pad place pad inc-string pad count type</lang>
And the second one like this:
<lang forth>s" 123" pad place pad 1 inc-string pad count type</lang>
Fortran
Using 'internal' files you can increment both integer and real strings <lang fortran>CHARACTER(10) :: intstr = "12345", realstr = "1234.5" INTEGER :: i REAL :: r
READ(intstr, "(I10)") i ! Read numeric string into integer i i = i + 1 ! increment i WRITE(intstr, "(I10)") i ! Write i back to string
READ(realstr, "(F10.1)") r r = r + 1.0 WRITE(realstr, "(F10.1)") r</lang>
FreeBASIC
<lang freebasic>' FB 1.05.0 Win64
Function Increment (num As String) As String
Dim d As Double = Val(num) Return Str(d + 1.0)
End Function
Dim num(5) As String = {"1", "5", "81", "123.45", "777.77", "1000"} For i As Integer = 0 To 5
Print num(i); " + 1", " = "; Increment(num(i))
Next
Print Print "Press any key to exit" Sleep</lang>
- Output:
1 + 1 = 2 5 + 1 = 6 81 + 1 = 82 123.45 + 1 = 124.45 777.77 + 1 = 778.77 1000 + 1 = 1001
Frink
The following works for integers, rational numbers, complex numbers, floating-point, etc. <lang frink>a = input["Enter number: "] toString[eval[a] + 1]</lang>
FutureBasic
<lang futurebasic> include "NSLog.incl"
CFStringRef s = @"12345" NSInteger i
for i = 1 to 10 NSLog( @"%ld", fn StringIntegerValue( s ) + i ) next HandleEvents </lang>
Output:
12346 12347 12348 12349 12350 12351 12352 12353 12354 12355
Fōrmulæ
Fōrmulæ programs are not textual, visualization/edition of programs is done showing/manipulating structures but not text. Moreover, there can be multiple visual representations of the same program. Even though it is possible to have textual representation —i.e. XML, JSON— they are intended for storage and transfer purposes more than visualization and edition.
Programs in Fōrmulæ are created/edited online in its website, However they run on execution servers. By default remote servers are used, but they are limited in memory and processing power, since they are intended for demonstration and casual use. A local server can be downloaded and installed, it has no limitations (it runs in your own computer). Because of that, example programs can be fully visualized and edited, but some of them will not run if they require a moderate or heavy computation/memory resources, and no local server is being used.
In this page you can see the program(s) related to this task and their results.
Gambas
Click this link to run this code <lang gambas>Public Sub Main() Dim vInput As Variant = "12345"
Inc vInput Print vInput
End</lang> Output:
12346
GAP
<lang gap># Using built-in functions Incr := s -> String(Int(s) + 1);
- Implementing addition
- (but here 9...9 + 1 = 0...0 since the string length is fixed)
Increment := function(s)
local c, n, carry, digits;
digits := "0123456789";
n := Length(s);
carry := true;
while n > 0 and carry do
c := Position(digits, s[n]) - 1;
if carry then
c := c + 1;
fi;
if c > 9 then
carry := true;
c := c - 10;
else
carry := false;
fi;
s[n] := digits[c + 1];
n := n - 1;
od;
end;
s := "2399"; Increment(s); s;
- "2400"</lang>
Go
Concise: <lang go>package main import "fmt" import "strconv" func main() {
i, _ := strconv.Atoi("1234")
fmt.Println(strconv.Itoa(i + 1))
}</lang> More: <lang go>package main
import (
"math/big" "fmt" "strconv"
)
func main() {
// integer
is := "1234"
fmt.Println("original: ", is)
i, err := strconv.Atoi(is)
if err != nil {
fmt.Println(err)
return
}
// assignment back to original variable shows result is the same type.
is = strconv.Itoa(i + 1)
fmt.Println("incremented:", is)
// error checking worthwhile
fmt.Println()
_, err = strconv.Atoi(" 1234") // whitespace not allowed
fmt.Println(err)
_, err = strconv.Atoi("12345678901")
fmt.Println(err)
_, err = strconv.Atoi("_1234")
fmt.Println(err)
_, err = strconv.ParseFloat("12.D34", 64)
fmt.Println(err)
// float
fmt.Println()
fs := "12.34"
fmt.Println("original: ", fs)
f, err := strconv.ParseFloat(fs, 64)
if err != nil {
fmt.Println(err)
return
}
// various options on FormatFloat produce different formats. All are valid
// input to ParseFloat, so result format does not have to match original
// format. (Matching original format would take more code.)
fs = strconv.FormatFloat(f+1, 'g', -1, 64)
fmt.Println("incremented:", fs)
fs = strconv.FormatFloat(f+1, 'e', 4, 64)
fmt.Println("what format?", fs)
// complex
// strconv package doesn't handle complex types, but fmt does.
// (fmt can be used on ints and floats too, but strconv is more efficient.)
fmt.Println()
cs := "(12+34i)"
fmt.Println("original: ", cs)
var c complex128
_, err = fmt.Sscan(cs, &c)
if err != nil {
fmt.Println(err)
return
}
cs = fmt.Sprint(c + 1)
fmt.Println("incremented:", cs)
// big integers have their own functions
fmt.Println()
bs := "170141183460469231731687303715884105728"
fmt.Println("original: ", bs)
var b, one big.Int
_, ok := b.SetString(bs, 10)
if !ok {
fmt.Println("big.SetString fail")
return
}
one.SetInt64(1)
bs = b.Add(&b, &one).String()
fmt.Println("incremented:", bs)
}</lang>
- Output:
original: 1234 incremented: 1235 strconv.ParseInt: parsing " 1234": invalid syntax strconv.ParseInt: parsing "12345678901": value out of range strconv.ParseInt: parsing "_1234": invalid syntax strconv.ParseFloat: parsing "12.D34": invalid syntax original: 12.34 incremented: 13.34 what format? 1.3340e+01 original: (12+34i) incremented: (13+34i) original: 170141183460469231731687303715884105728 incremented: 170141183460469231731687303715884105729
Golfscript
<lang golfscript>~)`</lang> With a test framework to supply a number: <lang golfscript>"1234" ~)` p</lang>
Groovy
Solution: <lang groovy>println ((("23455" as BigDecimal) + 1) as String) println ((("23455.78" as BigDecimal) + 1) as String)</lang>
- Output:
23456 23456.78
Haskell
<lang haskell>(show . (+1) . read) "1234"</lang>
or, for Integral values, we can use the Prelude's succ function:
<lang haskell>(show . succ) (read "1234" :: Int)</lang>
and to extend the range of a succString function to allow for both floating point and integral numeric strings, for non-numeric noise, for multiple numeric expressions within a single string, and for an option to retain or prune any non-numeric noise, we could write things like:
<lang haskell>import Text.Read (readMaybe) import Data.Maybe (mapMaybe)
succString :: Bool -> String -> String succString pruned s =
let succs
:: (Num a, Show a)
=> a -> Maybe String
succs = Just . show . (1 +)
go w
| elem '.' w = (readMaybe w :: Maybe Double) >>= succs
| otherwise = (readMaybe w :: Maybe Integer) >>= succs
opt w
| pruned = Nothing
| otherwise = Just w
in unwords $
mapMaybe
(\w ->
case go w of
Just s -> Just s
_ -> opt w)
(words s)
-- TEST ---------------------------------------------------
main :: IO ()
main =
(putStrLn . unlines) $ succString <$> [True, False] <*> pure "41.0 pine martens in 1491 -1.5 mushrooms ≠ 136"</lang>
- Output:
42.0 1492 -0.5 137 42.0 pine martens in 1492 -0.5 mushrooms ≠ 137
HicEst
<lang hicest>CHARACTER string = "123 -4567.89"
READ( Text=string) a, b WRITE(Text=string) a+1, b+1 ! 124 -4566.89</lang>
HolyC
<lang holyc>I8 *s;
s = "10"; s = Str2I64(s) + 1; Print("%d\n", s);
s = "-10"; s = Str2I64(s) + 1; Print("%d\n", s);</lang>
Hy
<lang clojure>(str (inc (int "123")))</lang> Alternatively, with the "threading" macro: <lang clojure>(-> "123" (int) (inc) (str))</lang>
HyperTalk
<lang hypertalk>put 0 into someVar add 1 to someVar -- without "into [field reference]" the value will appear -- in the message box put someVar -- into cd fld 1</lang>
i
<lang i>software { string = "1" string += 1 print(string) }</lang>
Icon and Unicon
Icon and Unicon will automatically coerce type conversions where they make sense. Where a conversion can't be made to a required type a run time error is produced.
<lang Icon>s := "123" # s is a string s +:= 1 # s is now an integer</lang>
IDL
<lang idl>str = '1234' print, string(fix(str)+1)
- ==> 1235</lang>
In fact, IDL tries to convert types cleverly. That works, too:
<lang idl>print, '1234' + 1
- ==> 1235</lang>
Inform 7
This solution works for numbers that fit into a single word (16-bit signed int for Z-machine, 32-bit signed int for Glulx virtual machine). <lang inform7>Home is a room.
To decide which indexed text is incremented (T - indexed text): let temp be indexed text; let temp be the player's command; change the text of the player's command to T; let N be a number; if the player's command matches "[number]": let N be the number understood; change the text of the player's command to temp; decide on "[N + 1]".
When play begins: say incremented "12345"; end the story.</lang>
Io
<lang>str := ("123" asNumber + 1) asString</lang>
J
<lang j>incrTextNum=: >:&.".</lang>
Note that in addition to working for a single numeric value, this will increment multiple values provided within the same string, on a variety of number types and formats including rational and complex numbers. <lang j> incrTextNum '34.5' 35.5
incrTextNum '7 0.2 3r5 2j4 5.7e_4'
8 1.2 1.6 3j4 1.00057</lang>
Note also that the result here is a list of characters, and not a list of integers, which becomes obvious when you manipulate the result. For example, consider the effect of reversing the contents of the list:
<lang j> |.incrTextNum'123 456' 754 421
|.1+123 456
457 124</lang>
Java
When using Integer.parseInt in other places, it may be beneficial to call trim on the String, since parseInt will throw an Exception if there are spaces in the String. <lang java>String s = "12345"; s = String.valueOf(Integer.parseInt(s) + 1);</lang>
Another solution that works with big decimal numbers: <lang java>String s = "123456789012345678901234567890.12345"; s = new BigDecimal(s).add(BigDecimal.ONE).toString();</lang>
JavaScript
ES6
Using implicit coercion:
<lang javascript>let s = '9999'; let splusplus = (+s+1)+""
console.log([splusplus, typeof splusplus]) // 10000,string</lang>
Or, expanding the range of a stringSucc function to allow for non-numeric noise, and also for multiple numeric expressions in a single string:
<lang javascript>(() => {
'use strict';
// succString :: Bool -> String -> String
const succString = blnPruned => s => {
const go = w => {
const
v = w.includes('.') ? (
parseFloat(w)
) : parseInt(w);
return isNaN(v) ? (
blnPruned ? [] : [w]
) : [(1 + v).toString()];
};
return unwords(concatMap(go, words(s)));
};
// TEST -----------------------------------------------
const main = () =>
console.log(
unlines(
ap(
map(succString, [true, false]),
['41 pine martens in 1491.3 -1.5 mushrooms ≠ 136']
)
)
);
// GENERIC FUNCTIONS ----------------------------------
// Each member of a list of functions applied to each // of a list of arguments, deriving a list of new values.
// ap (<*>) :: [(a -> b)] -> [a] -> [b]
const ap = (fs, xs) => //
fs.reduce((a, f) => a.concat(
xs.reduce((a, x) => a.concat([f(x)]), [])
), []);
// concatMap :: (a -> [b]) -> [a] -> [b]
const concatMap = (f, xs) =>
xs.reduce((a, x) => a.concat(f(x)), []);
// map :: (a -> b) -> [a] -> [b] const map = (f, xs) => xs.map(f);
// unlines :: [String] -> String
const unlines = xs => xs.join('\n');
// unwords :: [String] -> String
const unwords = xs => xs.join(' ');
// words :: String -> [String] const words = s => s.split(/\s+/);
// MAIN --- return main();
})();</lang>
- Output:
42 1492.3 -0.5 137 42 pine martens in 1492.3 -0.5 mushrooms ≠ 137
jq
tonumber
jq's string-to-number filter is called tonumber. For example, if we have a file named input.txt consisting of string representations of numbers, one per line, we could compute the sum as follows: <lang sh>$ jq -n -M -s 'map(tonumber) | add' input.txt</lang>
More precisely, tonumber will convert string representations of JSON numbers (integers and decimals) to numbers, but very large integers will be converted to decimals with possible loss of precision, and similar problems will be noticeable for very small and very large decimals.
tostring can be used to convert numbers to strings.
long_add
<lang jq># This function assumes its string arguments represent non-negative decimal integers. def long_add(num1; num2):
if (num1|length) < (num2|length) then long_add(num2; num1)
else (num1 | explode | map(.-48) | reverse) as $a1
| (num2 | explode | map(.-48) | reverse) as $a2
| reduce range(0; num1|length) as $ix
($a2; # result
( $a1[$ix] + .[$ix] ) as $r
| if $r > 9 # carrying
then
.[$ix + 1] = ($r / 10 | floor) +
(if $ix + 1 >= length then 0 else .[$ix + 1] end )
| .[$ix] = $r - ( $r / 10 | floor ) * 10
else
.[$ix] = $r
end )
| reverse | map(.+48) | implode
end ;</lang>
Example <lang jq> long_add("9" * 100; "1")</lang>
- Output:
"10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
Jsish
<lang javascript>var a = "1" a = String(Number(a) + 1)</lang>
Julia
<lang julia>import Base.+ Base.:+(s::AbstractString, n::Real) = string((x = tryparse(Int, s)) isa Int ? x + 1 : parse(Float64, s) + 1) @show "125" + 1 @show "125.15" + 1 @show "1234567890987654321" + 1
</lang>
- Output:
"125" + 1 = "126" "125.15" + 1 = "126.15" "1234567890987654321" + 1 = "1234567890987654322"
K
"." is a built-in function that evaluates a valid K expression.
<lang K> 1 + ."1234" 1235
1 + ."1234.56"
1235.56
/ As a function
inc:{1 + . x}
inc "1234"
1235</lang>
Some other examples. <lang K> 1 + .:' ("1";"2";"3";"4") 2 3 4 5
1 + . "123 456"
124 457
. "1","+","-10"
-9</lang>
Kotlin
<lang scala>// version 1.0.5-2
/** overload ++ operator to increment a numeric string */ operator fun String.inc(): String =
try {
val num = this.toInt()
(num + 1).toString()
}
catch(e: NumberFormatException) {
this // return string unaltered
}
fun main(args: Array<String>) {
var ns = "12345" println(++ns) ns = "ghijk" // not numeric, so won't be changed by increment operator println(++ns)
}</lang>
- Output:
12346 ghijk
Lambdatalk
<lang scheme> In lambdatalk every expression is a word or an S-expression, so:
{b hello world} // means "boldify the words hello and world" -> < b>hello world< /b> // HTML expression
{+ hello world} // means "add the words hello and world" -> NaN // can't do the job and returns Not a Number
{+ 123 1} // means "add the words 123 and 1" -> 124 // can do the job and returns the result as a word </lang>
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.
Lasso
<lang Lasso>(integer('123') + 1) -> asstring</lang> -> 124
LaTeX
<lang LaTeX>\documentclass{minimal} \newcounter{tmpnum} \newcommand{\stringinc}[1]{%
\setcounter{tmpnum}{#1}%
\stepcounter{tmpnum}%
\arabic{tmpnum}%
} \begin{document} The number 12345 is followed by \stringinc{12345}. \end{document}</lang>
Liberty BASIC
<lang lb>' [RC] Increment a numerical string.
o$ ="12345" print o$
v =val( o$) o$ =str$( v +1) print o$
end</lang>
LIL
<lang tcl>##
Increment a numerical string, in LIL
set a "41" inc a print $a</lang>
- Output:
prompt$ lil incrementNumericalString.lil 42
Lingo
<lang lingo>put integer("123")+1 -- 124</lang>
LiveCode
LiveCode casts types transparently. When storing a number in a variable, the internal representation is numeric (a double, I think), and if the variable is used as a number, there is no type conversion. If the variable is used as a string, the conversion is automatic; likewise if a string variable containing a number is used as a number: <lang LiveCode>put "0" & "1234" into myString -- I think this will result in an internal string representation add 1 to myString -- automatically converts to a number put "The number is:" && myString -- outputs "The number is: 1235"</lang>
Logo
Logo is weakly typed, so numeric strings can be treated as numbers and numbers can be treated as strings. <lang logo>show "123 + 1 ; 124 show word? ("123 + 1) ; true</lang>
Logtalk
<lang logtalk>number_chars(Number, "123"), Number2 is Number+1, number_chars(Number2, String2)</lang>
LOLCODE
LOLCODE is weakly typed, so the arithmetic operators work "as expected" on strings.
<lang LOLCODE>HAI 1.3
I HAS A foo ITZ "1234" foo R SUM OF foo AN 1 VISIBLE foo BTW, prints 1235
KTHXBYE</lang>
LSL
To test it yourself; rez a box on the ground, and add the following as a New Script. <lang LSL>default { state_entry() { llListen(PUBLIC_CHANNEL, "", llGetOwner(), ""); llOwnerSay("Say a Number and I'll Increment it."); } listen(integer iChannel, string sName, key kId, string sMessage) { llOwnerSay("You said '"+sMessage+"' + 1 = "+(string)(((integer)sMessage)+1)); } }</lang>
- Output:
Increment_a_Numerical_String: You said '99999999' + 1 = 100000000 Increment_a_Numerical_String: You said '-100000000' + 1 = -99999999
Lua
Lua will attempt an implicit type conversion if an arithmetic operator is used with a string. This is illustrated by the following interactive session (revised for Lua 5.4):
> -- A STRING THAT CAN BE IMPLICITLY CONVERTED TO A NUMBER
> s = "1234"
> s+1 -- implicitly convert to number, add 1, remain a number
1235
> type(s+1)
number
> (s+1)..'' -- implicitly convert to number, add 1, implicitly convert back to string
1235
> type((s+1)..'')
string
> tostring(s+1) -- implicitly convert to number, add 1, explicitly convert back to string
1235
> type(tostring(s+1))
string
> -- A STRING THAT CANNOT BE IMPLICITLY CONVERTED TO A NUMBER
> s = "hello"
> s+1
stdin:1: attempt to add a 'string' with a 'number'
stack traceback:
[C]: in metamethod 'add'
stdin:1: in main chunk
[C]: in ?
> -- ONE-LINER EXPLICIT VERSION
> tostring(tonumber("1234")+1)
1235
M2000 Interpreter
Using Str$( stringexpr, "") we trim leading space for positive numbers. We can use a number as locale id, 1032 for Greece, so Str$(12.1212, 1032) return without leading space "12,1212".
Str$(mumberexpression) return always dot for decimal point Val(stringexpression) read dot as decimal point Val(stringexpression, ",") use "," as decimal point Val(stringexpression, 1032) use Locale 1032 (maybe this can change by OS user), so we get "." or "," (the later is by default the decimal point for 1032).
We can use Eval("1212211212122112215@") which evaluate expressions in strings (among other duties when we use objects), and we can use letters to indicate the type of number Val can return type using a special form, using a numeric expression as first parameter: Local m=Val(112+1.12->Decimal) make a new variable m type of decimal (96-bit integer with a variable power of 10).
<lang M2000 Interpreter> Module CheckIt {
s$ = "12345"
s$ = STR$(VAL(s$) + 1,"")
Print S$
\\ using , for decimal point like in Locale 1032 for Greece
s$ = "123,45"
\\ we get value in Locale 1032
S$=Str$(VAL(s$,",") + 1, 1032)
} CheckIt </lang>
M4
M4 can handle only integer signed 32 bit numbers, and they can be only written as strings <lang m4>define(`V',`123')dnl define(`VN',`-123')dnl eval(V+1) eval(VN+1)</lang>
If the expansion of any macro in the argument of eval gives something that can't be interpreted as an expression, an error is raised (but the interpretation of the whole file is not stopped)
Maple
<lang maple>s := "12345"; s := convert(parse(s)+1, string);</lang>
Mathematica / Wolfram Language
<lang Mathematica>FromDigits["1234"] + 1</lang>
MATLAB
<lang MATLAB>function numStr = incrementNumStr(numStr)
numStr = num2str(str2double(numStr) + 1);
end</lang>
MAXScript
<lang maxscript>str = "12345" str = ((str as integer) + 1) as string</lang>
Metafont
<lang metafont>string s; s := "1234"; s := decimal(scantokens(s)+1); message s;</lang>
min
<lang min>(int succ string) :next</lang>
mIRC Scripting Language
<lang mirc>var %n = 12345 inc %n echo -ag %n</lang>
ML
mLite
<lang ocaml>ntos ` ston "1234" + 1; </lang>
Standard ML
<lang sml>Int.toString (1 + valOf (Int.fromString "1234"))</lang>
Modula-2
<lang modula2>MODULE addstr;
IMPORT InOut, NumConv, Strings;
VAR str1, str2 : Strings.String;
num : CARDINAL;
ok : BOOLEAN;
BEGIN
str1 := "12345";
InOut.Write ('"'); InOut.WriteString (str1); InOut.WriteString ('" + 1 = ');
NumConv.Str2Num (num, 10, str1, ok);
INC (num);
NumConv.Num2Str (num, 10, str2, ok);
InOut.WriteString (str2);
InOut.WriteLn
END addstr.</lang>
"12345" + 1 = 12346
Modula-3
Modula-3 provides the module Scan for lexing. <lang modula3>MODULE StringInt EXPORTS Main;
IMPORT IO, Fmt, Scan;
VAR string: TEXT := "1234";
num: INTEGER := 0;
BEGIN
num := Scan.Int(string); IO.Put(string & " + 1 = " & Fmt.Int(num + 1) & "\n");
END StringInt.</lang>
- Output:
1234 + 1 = 1235
MUMPS
Just add. MUMPS has strings of characters as its native datatype. The "+" (plus) binary operator interprets its two arguments as numbers, so the MUMPS system does incrementing a string naturally. MUMPS portability standards require that the result must have at least 15 significant digits. Some implementations use Binary Coded Digits (BCD) and long fixed point (64 bit) integers to accomplish this. <lang MUMPS>
SET STR="123" WRITE STR+1
</lang>
Nanoquery
<lang Nanoquery>num = "123" num = str(int(num) + 1)</lang>
Neko
<lang Neko>var str = "123"; var str = $string($int(str) + 1);
$print(str);</lang>
Nemerle
<lang Nemerle>mutable str = "12345"; str = $"$(Int32.Parse(str)+1)";</lang>
NetRexx
In concert with Rexx, NetRexx can use typeless variables. Typeless variable support is provided through the default NetRexx Rexx object. Values are stored as variable length character strings and can be treated as either a string or a numeric value, depending on the context in which they are used.
<lang NetRexx>/* NetRexx */
options replace format comments java crossref savelog symbols nobinary
numbers = '12345' say numbers numbers = numbers + 1 say numbers
return </lang>
- Output:
12345 12346
NewLISP
<lang NewLISP>(string (++ (int "123")))</lang>
Nim
<lang nim>import strutils let next = $(parseInt("123") + 1)</lang>
NS-HUBASIC
<lang NS-HUBASIC>10 S$ = "12345" 20 S$ = STR$(VAL(s$) + 1)</lang>
Oberon-2
<lang oberon2>MODULE addstr;
IMPORT Out, Strings;
VAR str1, str2 : ARRAY 9 OF CHAR;
num, pos : INTEGER;
carry : BOOLEAN;
ch : CHAR;
BEGIN
str1 := "9999";
Out.Char ('"'); Out.String (str1); Out.String ('" + 1 = ');
num := Strings.Length (str1) - 1;
pos := num;
IF str1 [0] = '9' THEN INC (pos) END;
str2 [pos + 1] := 0X;
carry := TRUE;
REPEAT
ch := str1 [num];
IF carry THEN
ch := CHR (ORD (ch) + 1)
END;
IF ch > '9' THEN
carry := TRUE;
ch := '0'
ELSE
carry := FALSE
END;
str2 [pos] := ch;
DEC (num);
DEC (pos)
UNTIL num < 0;
IF carry THEN str2 [0] := '1' END;
Out.String (str2);
Out.Ln
END addstr.</lang> Producing:
jan@Beryllium:~/Oberon/obc$ Add "12345" + 1 = 12346 "9999" + 1 = 10000
Objeck
<lang objeck> s := "12345"; i := int->ToInt(s) + 1; s := i->ToString(); </lang>
Objective-C
<lang objc>NSString *s = @"12345"; int i = [s intValue] + 1; s = [NSString stringWithFormat:@"%i", i]</lang>
OCaml
<lang ocaml>string_of_int (succ (int_of_string "1234"))</lang>
Octave
We convert the string to a number, increment it, and convert it back to a string.
<lang octave>nstring = "123"; nstring = sprintf("%d", str2num(nstring) + 1); disp(nstring);</lang>
Oforth
+ on strings is a concatenation, not an addition. To increment, the string is converted as integer then as string again.
<lang Oforth>"999" 1 + println "999" asInteger 1 + asString println</lang>
- Output:
9991 1000
OoRexx
ooRexx supports the += etc. operators: <lang oorexx>i=1 i+=1 Say i</lang>
- Output:
2
OpenEdge/Progress
<lang progress>DEFINE VARIABLE cc AS CHARACTER INITIAL "12345".
MESSAGE
INTEGER( cc ) + 1
VIEW-AS ALERT-BOX.</lang>
Oz
<lang oz>{Int.toString {String.toInt "12345"} + 1}</lang>
PARI/GP
<lang parigp>foo(s)=Str(eval(s)+1);</lang>
Pascal
See also Free Pascal and Delphi
<lang pascal> program TestIncNumString; type tMyNumString = string(20);
procedure IncMyString(var NumString: tMyNumString); var i: integer; begin readStr(NumString, i); writeStr(NumString, succ(i)) end; //example var
MyNumString :tMyNumString;
BEGIN
MyNumString := '12345'; write(MyNumString,' turns into '); IncMyString(MyNumString); write(MyNumString);
END.</lang>
- Output:
12345 turns into 12346
Free Pascal
not like Delphi doing two conversion, but increment a string by 1 is much faster. Here with different bases upto 10.After this there must be a correction to convert values > '9' to 'A'... Only for positive integer strings as high speed counter. <lang pascal>program StrInc; //increments a positive numerical string in different bases. //the string must be preset with a value, length >0 ; {$IFDEF WINDOWS}
{$APPTYPE CONSOLE}
{$ENDIF} {$IFDEF FPC}
{$Mode Delphi} {$Optimization ON,ALL}{$Align 32}
uses
sysutils;
{$ELSE}
uses system.SysUtils;
{$ENDIF} type
myString = AnsiString; // String[32];//
function IncLoop(ps: pChar;le,Base: NativeInt):NativeInt;inline; //Add 1 and correct carry //returns 0, if no overflow, else 1 var
dg: nativeInt;
Begin
dec(le);//ps is 0-based
dg := ord(ps[le])+(-ord('0')+1);
result := 0;
repeat
IF dg < base then
begin
ps[le] := chr(dg+ord('0'));
EXIT;
end;
ps[le] := '0';
dec(le);
dg := ord(ps[le])+(-ord('0')+1);
until (le<0);
result:= 1;
end;
procedure IncIntStr(base:NativeInt;var s:myString); var
le: NativeInt;
begin
le := length(s); //overflow -> prepend a '1' to string if (IncLoop(pChar(@s[1]),le,base) <>0) then Begin
// s := '1'+s;
setlength(s,le+1); move(s[1],s[2],le); s[1] := '1'; end;
end;
const
ONE_BILLION = 1000*1000*1000; strLen = 26; MAX = 1 shl strLen -1;
var
s : myString; i,base : nativeInt; T0: TDateTime;
Begin
writeln(MAX,' increments in base'); For base := 2 to 10 do Begin //s := '0' doesn't work setlength(s,1); s[1]:= '0';
{ //Zero pad string
setlength(s,strLen);fillchar(s[1],strLen,'0');
}
T0 := time;
For i := 1 to MAX do
IncIntStr(Base,s);
T0 := (time-T0)*86400;
writeln(s:strLen,' base ',base:2,T0:8:3,' s');
end;
writeln;
writeln('One billion digits "9"');
setlength(s,ONE_BILLION+1);
s[1]:= '0';//don't measure setlength in IncIntStr
fillchar(s[2],length(s)-1,'9');
writeln('first 5 digits ',s[1],s[2],s[3],s[4],s[5]);
T0 := time;
IncIntStr(10,s);
T0 := (time-T0)*86400;
writeln(length(s):10,T0:8:3,' s');
writeln('first 5 digits ',s[1],s[2],s[3],s[4],s[5]);
s:=;
{$IFDEF WINDOWS}
readln;
{$ENDIF}
end. </lang>
- @TIO.RUN:
//sys time for allocating 1 Gb
Real time: 5.512 s User time: 4.068 s Sys. time: 1.288 s CPU share: 97.17 %
67108863 increments in base
11111111111111111111111111 base 2 0.395 s
11200021111001110 base 3 0.351 s
3333333333333 base 4 0.301 s
114134440423 base 5 0.348 s
10354213103 base 6 0.290 s
1443262443 base 7 0.281 s
377777777 base 8 0.279 s
150244043 base 9 0.271 s
67108863 base 10 0.267 s
One billion digits "9"
first 5 digits 09999
1000000001 1.382 s
first 5 digits 10000
Perl
<lang perl>my $s = "12345"; $s++;</lang>
Phix
integer {{n}} = scanf("2047","%d") printf(1,"%d\n",{n+1})
- Output:
2048
Phixmonti
<lang Phixmonti>"12345" tonum 1 + tostr</lang>
PHP
<lang php>$s = "12345"; $s++;</lang>
Picat
parse_term/1
parse_term/1 is the best to use if there can be no assumption of the type of the number (integer or float). For integers to_int/1 is better to use, and for floats to_float/1.
<lang Picat>go =>
% integer Int = "123", println(int=Int), println(parse_term=Int.parse_term+1), println(to_int=Int.to_int+1), % assumes integer nl,
% float Float = "122.5", println(float=Float), println(parse_term=Float.parse_term+1), println(to_float=Float.to_float+1), nl.
</lang>
- Output:
int = 123 parse_term = 124 to_int = 124 float = 122.5 parse_term = 123.5 to_float = 123.5
parse_term/3
parse term/3 can evaluate numeric expressions with the help of apply/1:
<lang Picat>go2 =>
T = "2**16+1", println(t=T), parse_term(T,Term, _Vars), println(term=Term), println(apply=Term.apply).</lang>
- Output:
t = 2**16+1 term = 2 ** 16 + 1 apply = 65537
PicoLisp
<lang PicoLisp>(format (inc (format "123456")))</lang>
Pike
<lang Pike>string number = "0"; number = (string)((int)number+1); Result: "1"</lang>
PL/I
<lang pli>declare s picture '999999999'; s = '123456789'; s = s + 1; put skip list (s);</lang>
Note: SIZE is enabled by default in Windows PL/I. Therefore, with s='999999999', the SIZE condition is raised at execution time, and execution terminates.
Plain English
<lang plainenglish>To increment a numerical string: Convert the numerical string to a number. Add 1 to the number. Put the number into the numerical string.</lang>
Plain TeX
<lang tex>\newcount\acounter \def\stringinc#1{\acounter=#1\relax% \advance\acounter by 1\relax% \number\acounter} The number 12345 is followed by \stringinc{12345}. \bye</lang>
The generated page will contain the text:
The number 12345 is followed by 12346.
Pop11
<lang pop11>lvars s = '123456789012123456789999999999'; (strnumber(s) + 1) >< -> s;</lang>
PowerShell
The easiest way is to cast the string to int, incrementing it and casting back to string: <lang powershell>$s = "12345" $t = [string] ([int] $s + 1)</lang> One can also take advantage of the fact that PowerShell casts automatically according to the left-most operand to save one cast: <lang powershell>$t = [string] (1 + $s)</lang>
Prolog
Works with SWI-Prolog. <lang Prolog>incr_numerical_string(S1, S2) :- string_to_atom(S1, A1), atom_number(A1, N1), N2 is N1+1, atom_number(A2, N2), string_to_atom(S2, A2). </lang>
- Output:
<lang Prolog> ?- incr_numerical_string("123", S2). S2 = "124". </lang>
PureBasic
<lang PureBasic>string$="12345" string$=Str(Val(string$)+1) Debug string$</lang>
Python
<lang python>next = str(int('123') + 1)</lang>
Or, preserving the distinction between integer and floating point numeric values, while also allowing for noisy or multi-number numerical strings, and providing the option of retaining or pruning out any non-numeric parts of the string. <lang python># Dropping or keeping any non-numerics in the string
- succString :: Bool -> String -> String
def succString(blnPruned):
def go(x):
try:
return [str(1 + (float(x) if '.' in x else int(x)))]
except ValueError:
return [] if blnPruned else [x]
return lambda s: ' '.join(concatMap(go)(s.split()))
- TEST ----------------------------------------------------
def main():
print(
'\n'.join(
[succString(bln)(
'41.0 pine martens in 1491 -1.5 mushrooms ≠ 136'
) for bln in [False, True]]
)
)
- GENERIC ---------------------------------------------------
- concatMap :: (a -> [b]) -> [a] -> [b]
def concatMap(f):
return lambda xs: (
[ys[0] for ys in [f(x) for x in xs] if ys]
)
- MAIN ---
if __name__ == '__main__':
main()</lang>
- Output:
42.0 pine martens in 1492 -0.5 mushrooms ≠ 137 42.0 1492 -0.5 137
Quackery
As a dialogue in the Quackery shell.
$->n attempts to convert a string to an integer in the current base (default is decimal). It leaves 0 (i.e. false) on the top of the data stack if the string was not a valid integer, and 1 (i.e. true) if it was. Underneath the flag is the converted integer, or the routine's best guess, if the string was not a valid integer. When the first conversion fails, we can see in the problem report that the best guess was 12345.
/O> $ "1.2.3.4.5" $->n
... not if [ $ "not a valid integer" fail ]
... 1+
... number$ echo$
...
Problem: not a valid integer
Quackery Stack: 12345
Return stack: {[...] 0} {quackery 1} {[...] 11} {shell 5} {quackery 1} {[...] 4}
/O> $ "12345" $->n
... not if [ $ "not a valid integer" fail ]
... 1+
... number$ echo$
...
12346
Stack empty.
R
<lang r>s = "12345" s <- as.character(as.numeric(s) + 1)</lang>
Racket
<lang racket>
- lang racket
(define next (compose number->string add1 string->number)) </lang>
Raku
(formerly Perl 6)
<lang perl6>my $s = "12345"; $s++;</lang>
Rascal
<lang rascal> import String;
public str IncrNumStr(str s) = "<toInt(s) + 1>"; </lang>
- Output:
rascal>IncrNumStr("123")
str: "124"
REBOL
<lang REBOL>REBOL [ Title: "Increment Numerical String" URL: http://rosettacode.org/wiki/Increment_numerical_string ]
- Note the use of unusual characters in function name. Also note that
- because REBOL collects terms from right to left, I convert the
- string argument (s) to integer first, then add that result to one.
s++: func [s][to-string 1 + to-integer s]
- Examples. Because the 'print' word actually evaluates the block
- (it's effectively a 'reduce' that gets printed space separated),
- it's possible for me to assign the test string to 'x' and have it
- printed as a side effect. At the end, 'x' is available to submit to
- the 's++' function. I 'mold' the return value of s++ to make it
- obvious that it's still a string.
print [x: "-99" "plus one equals" mold s++ x] print [x: "42" "plus one equals" mold s++ x] print [x: "12345" "plus one equals" mold s++ x]</lang>
- Output:
-99 plus one equals "-98" 42 plus one equals "43" 12345 plus one equals "12346"
Retro
<lang Retro>'123 s:to-number n:inc n:to-string</lang>
REXX
REXX, like many other scripting languages, uses typeless variables.
Typeless variables are stored as variable length character strings and can be treated as
either a string or a numeric value, depending on the context in which they are used.
version 1
<lang rexx>/*REXX program demonstrates a method how to increment a numerical string*/ count = "3" /*REXX variables (and constants) are character strings.*/ count = 3 /*(identical to the above statement.) */ count = count+1 /*strings in a numerical context are treated as numbers*/ say 'sum=' count /*display the value of COUNT to the terminal (screen)*/
/*────────────────── The default numeric digits for REXX is 9 digits. */ /*────────────────── However, that can be increased with NUMERIC DIGITS.*/
numeric digits 15000 /*let's go ka-razy with fifteen thousand digits. */
count=copies(2,15000) /*stressing REXX's brains with lots of two's, */
/*the above is considered a number in REXX. */
count=count+3 /*make that last digit of COUNT a "5". */
if 1==0 then /*let's not display this gihugeic number to term,*/ say 'count=' count /*ya most likely don't want to display this thing*/
/* [↓] show the six leftmost and rightmost digs.*/
say 'count=' left(count,6)'···'right(count,6)
/*stick a fork in it, we're done.*/</lang>
- Output:
sum= 4 count= 222222···222225
version 2
Looking at the PL/I code I started investigating this situation in Rexx. These are my findings: <lang rexx>/* REXX ************************************************************
- There is no equivalent to PL/I's SIZE condition in REXX.
- The result of an arithmetic expression is rounded
- according to the current setting of Numeric Digits.
- ooRexx introduced, however, a LOSTDIGITS condition that checks
- if any of the OPERANDS exceeds this number of digits.
- Unfortunately this check is currently a little too weak
- and will not recognise a 10-digit number to be too large.
- This little bug will be fixed in the next release of ooRexx.
- /
Parse Version v . Say v z=999999998 Do i=1 To 3
z=z+1 Say z End
Numeric Digits 20 z=999999998 Do i=1 To 3
z=z+1 Say z End
Numeric Digits 9 If left(v,11)='REXX-ooRexx' Then
Signal On Lostdigits
z=100000000012 Say z z=z+1 Say z Exit lostdigits:
Say 'LOSTDIGITS condition raised in line' sigl
Say 'sourceline='sourceline(sigl)
Say "condition('D')="condition('D')</lang>
- Output:
REXX-ooRexx_4.1.2(MT)
999999999
1.00000000E+9
1.00000000E+9
999999999
1000000000
1000000001
100000000012
LOSTDIGITS condition raised in line 30
sourceline=z=z+1
condition('D')= 100000000012
Ring
<lang ring> x = "1234" See 1+x # print 1235 </lang>
Ruby
If a string represents a number, the succ method will increment the number: <lang ruby>'1234'.succ #=> '1235' '99'.succ #=> '100'</lang>
Run BASIC
Run BASIC has trim command for left and right <lang runbasic>string$ = "12345" numeric = val(string$) numeric = numeric + 1 string$ = str$(numeric) print string$ </lang>
12346
Rust
<lang rust>fn next_string(input: &str) -> String {
(input.parse::<i64>().unwrap() + 1).to_string()
}
fn main() {
let s = "-1";
let s2 = next_string(s);
println!("{:?}", s2);
}</lang>
- Output:
"0"
Scala
The string needs to be converted to a numeric type. BigDecimal should
handle most numeric strings. We define a method to do it.
<lang scala>implicit def toSucc(s: String) = new { def succ = BigDecimal(s) + 1 toString }</lang>
Usage:
scala> "123".succ res5: String = 124
Scheme
<lang scheme>(number->string (+ 1 (string->number "1234")))</lang>
Sed
Reads a decimal integer from stdin and outputs the same with the magnitude incremented by one.
(TODO: Since it deals only with the magnitude, the result is incorrect for negative numbers—though adding this support is definitely possible.)
The routine starts by suffixing the input number with a carry mark (a : in this case) indicating that the digit to its left still needs to be incremented. In a loop, the following happens:
- If there is a carry mark on the far left, replace it with a 1.
- If there are no more carry marks, exit the loop.
- Hold the current number. (
h) - Extract the digit to the left of the first carry mark. (
s) - Replace the digit with the same digit incremented by one, with 9 incrementing to a carry mark (i.e. 10). (
y) - If the result of such replacement was a carry mark, suffix the mark with a 0, indicating that the digit has rolled over and the digit to the left must be incremented. (
s) - Retrieve the held number (
G) and replace the first carry mark and the digit to its left with the result of the computation. (s) - Repeat. (
b)
<lang sed>s/^.*$/&:/
- bubble
s/^:/1/ /.:/ {
h s/^.*\(.\):.*$/\1/ y/0123456789/123456789:/ s/:/:0/ G s/\(.*\)\n\(.*\).:\(.*\)$/\2\1\3/ b bubble
}</lang>
Seed7
<lang seed7>var string: s is "12345";
s := str(succ(integer parse s));</lang>
SenseTalk
<lang sensetalk> put "123" + 1 // 124 </lang>
SequenceL
<lang sequencel>import <Utilities/Conversion.sl>;
increment(input(1)) := intToString(stringToInt(input) + 1);</lang>
Sidef
<lang ruby>say '1234'.inc; #=> '1235' say '99'.inc; #=> '100'</lang>
Slate
<lang slate>((Integer readFrom: '123') + 1) printString</lang>
Smalltalk
<lang smalltalk>('123' asInteger + 1) printString</lang> (a note to non-smalltalkers: "printString" does not print, but return the "printString")
SNOBOL4
<lang snobol4>
output = trim(input) + 1
output = "123" + 1
end</lang>
Input: 123 Output: 124 124
Sparkling
<lang sparkling>function numStrIncmt(s) {
return fmtstr("%d", toint(s) + 1);
}
spn:1> numStrIncmt("12345") = 12346</lang>
SuperTalk
<lang supertalk>put 0 into someVar add 1 to someVar -- without "into [field reference]" the value will appear -- in the message box put someVar -- into cd fld 1</lang>
Swift
<lang swift>let s = "1234" if let x = Int(s) {
print("\(x + 1)")
}</lang>
<lang swift>let s = "1234" if let x = s.toInt() {
println("\(x + 1)")
}</lang>
Tcl
In the end, all variables are strings in Tcl. A "number" is merely a particular interpretation of a string of bytes. <lang tcl>set str 1234 incr str</lang>
TI-83 BASIC
There is no single command to convert a number to a string; you have to store it to one of the Function variables which acts as both a number and a string. <lang ti83b>:"1"→Str1
- expr(Str1)+1→A
- {0,1}→L₁
- {0,A}→L₂
- LinReg(ax+b) Y₁
- Equ►String(Y₁,Str1)
- sub(Str1,1,length(Str1)-3)→Str1</lang>
TI-89 BASIC
<lang ti89b>string(expr(str)+1)</lang>
Toka
<lang toka>" 100" >number drop 1 + >string</lang>
TorqueScript
To increment by 1:
$string = "12345"; $string++;
$string is now 12346.
To increment by more than 1:
$string = "12345"; $string += 10;
$string is now 12355.
TUSCRIPT
<lang tuscript> $$ MODE TUSCRIPT teststring="0'1'-1'12345'10000000'-10000000" LOOP/CLEAR n=teststring n=n+1 PRINT n ENDLOOP </lang>
- Output:
1 2 0 12346 10000001 -9999999
TXR
Two implementations of what the task says: incrementing a numerical string. (Not: converting a string to a number, then incrementing the number, then converting back to string.)
TXR Lisp
<lang txr>@(do (defun inc-num-str (str-in)
(let ((len (length str-in))
(str (copy-str str-in)))
(for ((i (- len 1)))
((>= i 0) `1@str`)
((dec i))
(if (<= (inc [str i]) #\9)
(return str)
(set [str i] #\0))))))
@(bind a @(inc-num-str "9999")) @(bind b @(inc-num-str "1234"))</lang>
$ ./txr -B incnum.txr a="10000" b="1235"
No TXR Lisp
<lang txr>@(deffilter incdig ("0" "1") ("1" "2") ("2" "3") ("3" "4") ("4" "5")
("5" "6") ("6" "7") ("7" "8") ("8" "9"))
@(define increment (num out)) @ (local prefix dig junk) @ (next :string num) @ (cases) 9 @ (bind out "10") @ (or) @*{prefix}@{dig /[0-8]/} @ (bind out `@prefix@{dig :filter incdig}`) @ (or) @*{prefix}9 @ (bind out `@{prefix :filter (:fun increment)}0`) @ (or) @junk @ (throw error `bad input: @junk`) @ (end) @(end) @in @(increment in out)</lang>
$ echo 1 | ./txr -B incnum.txr - input="1" result="2" $ echo 123 | ./txr -B incnum.txr - input="123" result="124" $ echo 899999 | ./txr -B incnum.txr - input="899999" result="900000" $ echo 999998 | ./txr -B incnum.txr - input="999998" result="999999" $ echo 999999 | ./txr -B incnum.txr - input="999999" result="1000000"
UNIX Shell
Traditional Unix shell does not directly support arithmetic operations, so external tools, such as expr are used to perform arithmetic calculations when required. The following example demonstrates how a variable can be incremented by using the expr function:
<lang bash># All variables are strings within the shell
- Although num look like a number, it is in fact a numerical string
num=5 num=`expr $num + 1` # Increment the number</lang>
The Korn Shell and some newer shells do support arithmetic operations directly, and several syntax options are available:
<lang bash>num=5 let num=num+1 # Increment the number let "num = num + 1" # Increment again. (We can use spaces inside quotes) ((num = num + 1)) # This time we use doublebrackets let num+=1 # This time we use += let "num += 1" ((num += 1))</lang>
<lang bash>integer num=5 # Declare an integer... num=$num+1 # ...then increment without the let keyword.</lang>
C Shell
The @ assignment command uses strings as integers.
<lang csh>@ num = 5
@ num += 1</lang>
Ursa
<lang ursa>decl string num set num "123" set num (int (+ (int num) 1))</lang>
Ursala
<lang Ursala>#import nat
instring = ~&h+ %nP+ successor+ %np@iNC # convert, do the math, convert back</lang> test program: <lang Ursala>#cast %sL
tests = instring* <'22435','4','125','77','325'></lang>
- Output:
<'22436','5','126','78','326'>
VBA
The easy method assumes that the number can be represented as a Long integer: <lang VBA> Public Function incr(astring As String) As String 'simple function to increment a number string
incr = CStr(CLng(astring) + 1)
End Function </lang> Examples:
print incr("345343434")
345343435
print incr("-10000000")
-9999999
The long version handles arbitrary-length strings: <lang VBA> Public Function Lincr(astring As String) As String 'increment a number string, of whatever length 'calls function "increment" or "decrement" Dim result As String
'see if it is a negative number If left$(astring, 1) = "-" Then
'negative x: decrease |x| by 1, then add "-" '(except if the result is zero) result = decrement(Mid$(astring, 2)) If result <> "0" Then result = "-" & result
Else
'0 or positive x: increase x by 1 If left$(astring, 1) = "+" Then 'allow a + before the number result = increment(Mid$(astring, 2)) Else result = increment(astring) End If
End If Lincr = result End Function
Public Function increment(astring) As String Dim result As String 'increment a string representing a positive number 'does not work with negative numbers carry = 1 L = Len(astring) result = "" For j = L To 1 Step -1
digit = Val(Mid$(astring, j, 1)) + carry If digit > 9 Then digit = digit - 10 carry = 1 Else carry = 0 End If result = CStr(digit) & result
Next If carry = 1 Then result = CStr(carry) & result increment = result End Function
Public Function decrement(astring) As String Dim result As String 'decrement a string representing a positive number 'does not work with zero or negative numbers borrow = 1 L = Len(astring) result = "" For j = L To 1 Step -1
digit = Val(Mid$(astring, j, 1)) - borrow If digit < 0 Then digit = digit + 10 borrow = 1 Else borrow = 0 End If result = CStr(digit) & result
Next 'remove leading zero, if necessary If (Len(result) > 1) And (left$(result, 1) = "0") Then result = Mid$(result, 2) decrement = result End Function </lang> Examples:
print Lincr("99999999999999999")
100000000000000000
print Lincr("-10000000000000000")
-9999999999999999
print Lincr("-1")
0
print Lincr("0")
1
print Lincr("+1234567890987654321009")
1234567890987654321010
Vedit macro language
This example increments numeric string by converting it into numeric value, as most other language examples do. The string is located in text register 10. <lang vedit>itoa(atoi(10)+1, 10)</lang>
The following example increments unsigned numeric string of unlimited length. The current line in the edit buffer contains the string. <lang vedit>EOL do {
if (At_BOL) {
Ins_Char('1') // add new digit Break
}
Char(-1)
#1 = Cur_Char+1 // digit
#2 = 0 // carry bit
if (#1 > '9') {
#1 = '0' #2 = 1
} Ins_Char(#1, OVERWRITE) Char(-1)
} while (#2) // repeat until no carry</lang>
Visual Basic .NET
<lang vbnet> Dim s As String = "123"
s = CStr(CInt("123") + 1)
' or
s = (CInt("123") + 1).ToString</lang>
Vlang
<lang go>// Increment a numerical string in V module main
// V int conversion will give 0 for nonnumeric strings pub fn main() {
mut numstr := "-5"
print("numstr: ${numstr:-5} ")
numstr = (numstr.int()+1).str()
println("numstr: $numstr")
// Run a few tests
for testrun in ["0", "100", "00110", "abc", "41"] {
print("numstr: $testrun ")
numstr = (testrun.int()+1).str()
println("numstr: $numstr")
}
}</lang>
- Output:
prompt$ v run increment-a-numerical-string.v numstr: -5 numstr: -4 numstr: 0 numstr: 1 numstr: 100 numstr: 101 numstr: 00110 numstr: 111 numstr: abc numstr: 1 numstr: 41 numstr: 42
Wren
<lang ecmascript>var ns = "41" var n = Num.fromString(ns) + 1 var ns2 = "%(n)" System.print("%(ns) + 1 = %(ns2)")</lang>
- Output:
41 + 1 = 42
XLISP
<lang lisp>(DEFUN INCREMENT-STRING (X)
(NUMBER->STRING (+ (STRING->NUMBER X) 1)))</lang>
XPL0
<lang XPL0>string 0; \use zero-terminated string convention code Text=12;
func StrLen(A); \Return number of characters in an ASCIIZ string char A; int I; for I:= 0 to -1>>1-1 do
if A(I) = 0 then return I;
proc IncStr(S); \Increment a numeric string char S; int I; [for I:= StrLen(S)-1 downto 0 do
[S(I):= S(I)+1;
if S(I) > ^9 then S(I):= S(I)-10 else return;
];
];
char Str; [Str:= "0123999999999"; \MSD first (big endian) IncStr(Str); IncStr(Str); Text(0, Str); ]</lang>
- Output:
0124000000001
Z80 Assembly
It's much easier to do this using binary-coded decimal thanks to the DAA instruction.
<lang z80>;;;;;;;;;;ca;;;;;;;;; HEADER ;;;;;;;;;;;;;;;;;;;
read "\SrcCPC\winape_macros.asm"
read "\SrcCPC\MemoryMap.asm"
read "\SrcALL\winapeBuildCompat.asm"
- PROGRAM ;;;;;;;;;;;;;;;;;;;
org &1000
ld hl,NumericString
incstring: ld a,(hl) cp 255 jr z,displaystring add &01 daa ld (hl),a jr nc,displaystring
- carry forward
inc hl jr incstring
displaystring: ld hl,NumericString_End dec hl disploop: ld a,(hl) cp 255 ret z call showhex dec hl jr disploop
db 255 ;terminator when reading in reverse NumericString:
- stored little-endian for convenience
db &99,&99,&99,&01 NumericString_End: db 255 ;terminator
read "\SrcCPC\winape_showhex.asm" read "\SrcCPC\winape_stringop.asm"</lang>
zkl
In zkl, the first operand "wins" and transforms the second. So 5+"1"-->6 <lang zkl>fcn numStringPlusOne(s){1+s} numStringPlusOne("123") //-->124</lang>
Zoea
<lang Zoea> program: increment_a_numerical_string
case: 1 input: '1234' output: '1235' case: 2 input: '19' output: '20'
</lang>
