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A+B - in programming contests, classic problem, which is given so contestants can gain familiarity with online judging system being used.

A+B is one of few problems on contests, which traditionally lacks fabula.

Problem statement
Given 2 integer numbers, A and B. One needs to find their sum.

Input data

Two integer numbers are written in the input stream, separated by space.

(-1000\leq A,B\leq +1000)

Output data

The required output is one integer: the sum of A and B.

Example:

Input	Output
`2 2`	`4`
`3 2`	`5`

ALGOL 68

Translation of: python

Works with: ALGOL 68 version Standard - no extensions to language used

Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny

Console

<lang algol68>print((read int + read int))</lang> Input:

1 2

Output:

+3

File

<lang algol68>open(stand in, "input.txt", stand in channel); open(stand out, "output.txt", stand out channel); print((read int + read int))</lang> Input "input.txt":

3 4

Output "output.txt":

+7

Argile

Translation of: C

Works with: Argile version 1.0.0

<lang Argile>(: Standard input-output streams :) use std, array Cfunc scanf "%d%d" (&val int a) (&val int b) printf "%d\n" (a + b)</lang> <lang Argile>(: Input file : input.txt :) (: Output file: output.txt :) use std, array let in = fopen "input.txt" "r" let out = fopen "output.txt" "w" let int x, y. Cfunc fscanf in "%d%d" (&x) (&y) (:fscanf not yet defined in std.arg:) fprintf out "%d\n" (x+y) fclose in fclose out</lang>

AutoHotkey

<lang AutoHotkey>InputBox, input , A+B, Two integer numbers`, separated by space. StringSplit, output, input, %A_Space% msgbox, % output1 . "+" . output2 "=" output1+output2</lang>

AWK

<lang awk> {print $1 + $2} </lang>

Bash

Batch File

Prompts version

<lang dos>::aplusb.cmd @echo off setlocal set /p a="A: " set /p b="B: " set /a c=a+b echo %c% endlocal</lang>

All on the commandline version

<lang dos>::aplusb.cmd @echo off setlocal set a=%1 set b=%2 set /a c=a+b echo %c% endlocal</lang>

Formula on the command line version

<lang dos>::aplusb.cmd @echo off setlocal set /a c=%~1 echo %c% endlocal</lang>

Example of 'Formula on the command line version'

>aplusb 123+456
579
>aplusb "1+999"
1000

Parse the input stream version (thanks to Tom Lavedas on alt.msdos.batch.nt)

<lang dos>::aplusb.cmd @echo off setlocal set /p a="Input stream: " call :add %a% echo %res% endlocal goto :eof

add

set /a res=res+%1 shift if "%1" neq "" goto :add</lang>

Example of 'parse the input stream version'

>aplusb
Input stream: 1234 5678
6912
>aplusb
Input stream: 123 234 345 456 567 678 789 890
4082

BASIC

<lang qbasic>DEFINT A-Z

tryagain: backhere = CSRLIN INPUT "", i$ i$ = LTRIM$(RTRIM$(i$)) where = INSTR(i$, " ") IF where THEN

   a = VAL(LEFT$(i$, where - 1))
   b = VAL(MID$(i$, where + 1))
   c = a + b
   LOCATE backhere, LEN(i$) + 1
   PRINT c

ELSE

   GOTO tryagain

END IF</lang>

Befunge

Brainf***

C

<lang c>// Standard input-output streams

include <stdio.h>

int main() {

  int a, b;
  scanf("%d%d", &a, &b);
  printf("%d\n", a + b);
  return 0;

}</lang> <lang c>// Input file: input.txt // Output file: output.txt

include <stdio.h>

int main() {

  freopen("input.txt", "rt", stdin);
  freopen("output.txt", "wt", stdout);
  int a, b;
  scanf("%d%d", &a, &b);
  printf("%d\n", a + b);
  return 0;

}</lang>

C++

<lang cpp>// Standard input-output streams

include <iostream>

using namespace std; int main() {

  int a, b;
  cin >> a >> b;
  cout << a + b << endl;
  return 0;

}</lang> <lang cpp>// Input file: input.txt // Output file: output.txt

include <fstream>

using namespace std; int main() {

  ifstream in("input.txt");
  ofstream out("output.txt");
  int a, b;
  in >> a >> b;
  out << a + b << endl;
  return 0;

}</lang>

C_sharp

<lang csharp>using System.IO;

class plus { public static void Main(string[] args) { int a,b; { StreamReader reader = new StreamReader("plus.in"); a = int.Parse(reader.ReadLine()); b = int.Parse(reader.ReadLine()); StreamWriter writer = new StreamWriter("plus.out"); writer.WriteLine(a+b); writer.Close(); } } }</lang>

Clojure

<lang clojure> (println (+ (Integer/parseInt (read-line)) (Integer/parseInt (read-line)))) 3 4 =>7 </lang>

<lang clojure> (eval (read-string (str "(+ " (read-line) " )") )) 3 3 6 </lang>

Common Lisp

<lang lisp>(format t (write-to-string (+ (read) (read))))</lang>

D

As in the Python version.

Console

<lang d>import std.stdio: readln, writeln; import std.conv: to; import std.string: split;

void main() {

   auto r = readln().split();
   writeln(to!int(r[0]) + to!int(r[1]));

}</lang>

File

<lang d>import std.stdio: writeln, File; import std.conv: to; import std.string: split;

void main() {

   auto fin = File("input.txt", "r");
   auto fout = File("output.txt", "w");
   auto r = fin.readln().split();
   fout.writeln(to!int(r[0]) + to!int(r[1]));

}</lang>

DMS

<lang DMS> number a = GetNumber( "Please input 'a'", a, a ) // prompts for 'a' number b = GetNumber( "Please input 'b'", b, b ) // prompts for 'b' Result( a + b + "\n" ) </lang>

F#

<lang fsharp>open System let plus = (fun (a:string) (b:string) -> Console.WriteLine(int(a)+int(b))) (Console.ReadLine()) (Console.ReadLine());;</lang>

Factor

<lang factor>USING: math.parser splitting ;

a+b ( -- )

   readln " " split1
   [ string>number ] bi@ +
   number>string print ;</lang>

( scratchpad ) a+b
2 2
4

FALSE

<lang false>[0[^$$'9>'0@>|~]['0-\10*+]#%]n: {read an integer} n;!n;!+.</lang>

Forth

<lang Forth>pad dup 80 accept evaluate + .</lang>

Fortran

<lang fortran>program a_plus_b

 implicit none
 integer :: a
 integer :: b

 read (*, *) a, b
 write (*, '(i0)') a + b

end program a_plus_b</lang>

Golfscript

Haskell

<lang haskell>sum' :: [Char] -> Int sum' = sum . map read . words

main = getLine >>= (\xs -> print $ sum' xs)</lang>

HicEst

A and B are input via edit controls with spinners limiting inputs to +-1000. <lang HicEst>DLG(Edit=A, DNum, MIn=-1000, MAx=1000, E=B, DN, MI=-1000, MA=1000) WRITE(Messagebox, Name) A, B, "Sum = ", A+B</lang>

Icon and Unicon

Icon

<lang icon>procedure main()

    numChars := '-'++&digits
    read() ? {
        A := (tab(upto(numChars)), integer(tab(many(numChars))))
        B := (tab(upto(numChars)), integer(tab(many(numChars))))
        }
    write((\A + \B) | "Bad input")

end</lang>

Unicon

The Icon solution also works in Unicon.

J

Typically, in J, you would find the sum of two numbers (let us say 2 and 3) by entering both of them on a line with a + sign between them:

In the following expression, 1!:1(3) reads a line from STDIN; -.LF drops the line ending character; ". converts the remaining text to a sequence of numbers which are then summed using +/. <lang J>+/". (1!:1(3))-.LF</lang> Here's a little script, called "a+b.ijs": <lang J>#!/Applications/j602/bin/jconsole echo +/". (1!:1(3))-.LF exit </lang> Here is the execution of the script: <lang>echo 2 3 | ./a+b.ijs 5</lang>

Java

<lang java>import java.util.*;

public class Sum2 {

  public static void main(String[] args) {
     Scanner in = new Scanner(System.in); // Standard input
     System.out.println(in.nextInt() + in.nextInt()); // Standard output
  }

}</lang> Object of class Scanner works slow enough, because of that contestants prefer to avoid its use. Often, longer solution works faster and easily scales to problems.

<lang java>import java.io.*; import java.util.*;

public class SumDif {

  StreamTokenizer in;
  PrintWriter out;

  public static void main(String[] args) throws IOException {
     new SumDif().run();
  }

  private int nextInt() throws IOException {
     in.nextToken();
     return (int)in.nval;
  }

  public void run() throws IOException {
     in = new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in))); // Standard input
     out = new PrintWriter(new OutputStreamWriter(System.out)); // Standard output
     solve();
     out.flush();
  }

  private void solve() throws IOException {
     out.println(nextInt() + nextInt());
  }

}</lang>

<lang java>import java.io.*;

public class AplusB { public static void main(String[] args) { try { StreamTokenizer in = new StreamTokenizer(new FileReader("input.txt")); in.nextToken(); int a = (int) in.nval; in.nextToken(); int b = (int) in.nval; FileWriter outFile = new FileWriter("output.txt"); outFile.write(Integer.toString(a + b)); outFile.close(); } catch (IOException e) { System.out.println("IO error"); } } }</lang>

JavaScript

Works with: Firefox version 3

   var input = window.prompt('enter two integers, separated by whitespace',);
   document.getElementById('input').innerHTML = input;

   var sum = input.split(/\s+/).reduce( function(sum, str) {return sum + parseInt(str)}, 0);
   document.getElementById('output').innerHTML = sum;

</script> </body> </html></lang>

Liberty BASIC

<lang lb>input, n$ print eval(word$(n$,1);" + ";word$(n$,2))</lang>

Logo

<lang logo>show apply "sum readlist</lang>

Lua

<lang Lua>a,b = io.read("*number", "*number") print(a+b)</lang>

Mathematica

Interactive in a notebook

<lang Mathematica>Input[] + Input[]</lang>

MATLAB

<lang MATLAB> function sumOfInputs = APlusB()

   inputStream = input('Enter two numbers, separated by a space: ', 's');
   numbers = str2num(inputStream);                         %#ok<ST2NM>
   if any(numbers < -1000 | numbers > 1000)
       warning('APlusB:OutOfRange', 'Some numbers are outside the range');
   end
   sumOfInputs = sum(numbers);

end </lang>

MUMPS

<lang MUMPS> ANB

NEW A,B,T,S
READ !,"Input two integers between -1000 and 1000, separated by a space: ",S
SET A=$PIECE(S," ",1),B=$PIECE(S," ",2)
SET T=(A>=-1000)&(A<=1000)&(B>=-1000)&(B<=1000)&(A\1=A)&(B\1=B) 
IF T WRITE !,(A+B)
IF 'T WRITE !,"Bad input"
QUIT

</lang>

Objeck

<lang objeck> bundle Default {

 class Hello {
   function : Main(args : String[]) ~ Nil {
     line := IO.Console->GetInstance()->ReadString()->Trim();
     split := line->Find(' ');
     if(split > 0) {
       l := line->SubString(split);
       r := line->SubString(split + 1, line->Size() - split - 1);
       (l->ToInt() + r->ToInt())->PrintLine();
     };
   }
 }

} </lang>

OCaml

<lang ocaml>Scanf.scanf "%d %d" (fun a b -> Printf.printf "%d\n" (a + b))</lang>

Oz

<lang oz>declare

 class TextFile from Open.file Open.text end

 StdIn = {New TextFile init(name:stdin)}

 fun {ReadInt}
    {String.toInt {StdIn getS($)}}
 end

in

 {Show {ReadInt}+{ReadInt}}</lang>

PARI/GP

User input: <lang>input()+input()</lang>

File input: <lang>read("file1")+read("file2")</lang>

Pascal

<lang pascal>var

  a, b: integer;

begin

  readln(a, b);
  writeln(a + b);

end.</lang> Same with input from file input.txt and output from file output.txt. <lang pascal>var

  a, b: integer;

begin

  reset(input, 'input.txt');
  rewrite(output, 'output.txt');
  readln(a, b);
  writeln(a + b);
  close(input);
  close(output);

end.</lang>

Perl

<lang Perl>my ($a,$b) = split(/\D+/,<STDIN>); print "$a $b " . ($a + $b) . "\n";</lang>

Perl 6

<lang perl6>my ($a,$b) = $*IN.get.words; say $a+$b;</lang>

or, using the reduction meta operator: <lang perl6>say [+] $*IN.get.words</lang>

PHP

<lang php> fscanf(STDIN, "%d %d\n", $a, $b); //Reads 2 numbers from STDIN echo ($a + $b) . "\n"; </lang> <lang php> $in = fopen("input.dat", "r"); fscanf($in, "%d %d\n", $a, $b); //Reads 2 numbers from file $in fclose($in);

$out = fopen("output.dat", "w"); fwrite($out, ($a + $b) . "\n"); fclose($out); </lang>

PicoLisp

Piet

The code is fairly straightforward. The individual commands are as follows: <lang text>in(num) in(num) add out(num)</lang>

PostScript

PowerShell

<lang powershell>$a,$b = -split "$input" [int]$a + [int]$b</lang> This solution does not work interactively, while the following only works interactively: <lang powershell>$a,$b = -split (Read-Host) [int]$a + [int]$b</lang>

Prolog

Works with SWI-Prolog <lang Prolog>plus :-

   read_line_to_codes(user_input,X),
   atom_codes(A, X),
   atomic_list_concat(L, ' ', A),
   maplist(atom_number, L, LN),
   sumlist(LN, N),
   write(N).

</lang> output : <lang Prolog>?- plus. |: 4 5 9 true.</lang>

Pure

<lang pure>using system; printf "%d\n" (x+y) when x,y = scanf "%d %d" end; </lang>

PureBasic

Console

<lang PureBasic>x$=Input() a=Val(StringField(x$,1," ")) b=Val(StringField(x$,2," ")) PrintN(str(a+b))</lang>

File

<lang PureBasic>If ReadFile(0,"in.txt")

 x$=ReadString(0)
 a=Val(StringField(x$,1," "))
 b=Val(StringField(x$,2," "))
 If OpenFile(1,"out.txt")
   WriteString(1,str(a+b))
   CloseFile(1)
 EndIf
 CloseFile(0)

EndIf </lang>

Python

Console

<lang python>try: raw_input except: raw_input = input

print(sum(int(x) for x in raw_input().split()))</lang>

File

<lang python>fin = open("input.txt", "r") fout = open("output.txt","w") r = fin.readline().split() fout.write(str(int(r[0]) + int(r[1])))</lang>

R

Translation of: MATLAB

<lang r> a_plus_b <- function() {

 input_stream <- readline("Enter two numbers, separated by a space: ")
 numbers <- as.numeric(strsplit(input_stream, " ")1)
 if(any(numbers < -1000 || numbers > 1000)) 
 {
   warning("Some numbers are outside the range")
 }
 sum(numbers)

}

a_plus_b() </lang>

REBOL

<lang rebol>forever [x: load input print x/1 + x/2]</lang>

Sample output:

REXX

Retro

<lang Retro>: try ( "-n ) getToken toNumber getToken toNumber + putn ;</lang>

Ruby

<lang ruby>puts gets.split.map{|x| x.to_i}.inject{|sum, x| sum + x}</lang>

Works with: Ruby version 1.8.7+

<lang ruby>puts gets.split.map(&:to_i).inject(&:+)</lang>

Scala

<lang scala>println(readLine() split " " take 2 map (_.toInt) sum)</lang>

Scheme

<lang scheme>(write (+ (read) (read)))</lang>

sed

<lang sed>: Loop

All done

/^-*00* /s/// / -*00*$/s/// t

Negative Check

/^$-*$[0-9].* \1[0-9]/!b Negative

Create magic lookup table

s/$.[0-9]*$ $.[0-9]*$/\1;987654321000009999000999009909 \2;012345678999990000999000990090/ s/ $-$*$9*;$/ \10\2/

Decrement 1st number

s/$[^0]$$0*$;[^0]*\1$.$.*\2$9*$.* $.*$/\3\4 \5/

Increment 2nd

s/$[^9]$$9*$;[^9]*\1$.$.*\2$0*$.*/\3\4/ t Loop

Negative

Create magic lookup table

s/$.[0-9]*$ $.[0-9]*$/\1;987654321000009999000999009909 \2;987654321000009999000999009909/

Decrement 1st number

s/$[^0]$$0*$;[^0]*\1$.$.*\2$9*$.* $.*$/\3\4 \5/

Decrement 2nd

s/$[^0]$$0*$;[^0]*\1$.$.*\2$9*$.*/\3\4/ t Loop</lang>

SNOBOL4

Simple-minded solution (literally "two somethings separated by space") <lang snobol> input break(" ") . a " " rem . b output = a + b end</lang>

"Integer aware" solution: <lang snobol> nums = "0123456789" input span(nums) . a break(nums) span(nums) . b output = a + b end</lang>

SPARK

<lang Ada>-- By Jacob Sparre Andersen -- Validates with SPARK GPL 2010's Examiner/Simplifier

with SPARK_IO; --# inherit SPARK_IO;

--# main_program; procedure A_Plus_B --# global in out SPARK_IO.Inputs, SPARK_IO.Outputs; --# derives SPARK_IO.Inputs from SPARK_IO.Inputs & --# SPARK_IO.Outputs from SPARK_IO.Inputs, SPARK_IO.Outputs; is

  subtype Small_Integers is Integer range -1_000 .. +1_000;
  A, B       : Integer;
  A_OK, B_OK : Boolean;

begin

  SPARK_IO.Get_Integer 
    (File  => SPARK_IO.Standard_Input,
     Item  => A,
     Width => 0,
     Read  => A_OK);
  
  A_OK := A_OK and A in Small_Integers;
  
  SPARK_IO.Get_Integer 
    (File  => SPARK_IO.Standard_Input,
     Item  => B,
     Width => 0,
     Read  => B_OK);
  
  B_OK := B_OK and B in Small_Integers;
  
  if A_OK and B_OK then
     SPARK_IO.Put_Integer 
       (File  => SPARK_IO.Standard_Output,
        Item  => A + B,
        Width => 4,
        Base  => 10);
  else
     SPARK_IO.Put_Line 
       (File => SPARK_IO.Standard_Output,
        Item => "Input data does not match specification.",
        Stop => 0);
  end if;

end A_Plus_B; </lang>

SQL

<lang sql>select A+B</lang>

Example:

<lang sql>select 2+3</lang>

This should produce a result set containing the value 5.

Note however that declaration of variables is outside the scope of the ANSI SQL standards, unless by variables you mean tables (which would complicate the example considerably).

Tcl

<lang tcl>scan [gets stdin] "%d %d" x y puts [expr {$x + $y}]</lang> Alternatively: <lang tcl>puts [tcl::mathop::+ {*}[gets stdin]]</lang> To/from a file: <lang tcl>set in [open "input.txt"] set out [open "output.txt" w] scan [gets $in] "%d %d" x y puts $out [expr {$x + $y}] close $in close $out</lang>

TI-83 BASIC, TI-89 BASIC

<lang ti83b>:Prompt A,B

Disp A+B</lang>

UNIX Shell

Script "a+b.sh": <lang bash>#!/bin/sh read a b echo $(( a + b ))</lang> Output: <lang bash>echo 2 3 | ./a+b.sh 5</lang>

Ursala

Using standard input and output streams: <lang Ursala>#import std

import int

executable&

main = %zP+ sum:-0+ %zp*FiNCS+ sep` @L</lang> Overwriting a text file named as a command line parameter: <lang Ursala>#import std

import int

executable -[parameterized]-

main = ~command.files.&h; <.contents:= %zP+ sum:-0+ %zp*FiNCS+ sep` @L+ ~contents></lang> Creating a new file named after the input file with suffix .out: <lang Ursala>#import std

import int

executable -[parameterized]-

main =

~command.files.&h; ~&iNC+ file$[

  contents: %zP+ sum:-0+ %zp*FiNCS+ sep` @L+ ~contents,
  path: ~path; ^|C\~& ~=`.-~; ^|T/~& '.out'!]</lang>

X86 Assembly

Works with: NASM version Linux

<lang asm> section .text global _start

_print: mov ebx, 1 mov eax, 4 int 0x80 ret

_get_input: mov edx, 4 mov ebx, 0 mov eax, 3 int 0x80 ret

_start: mov edx, in_val_len mov ecx, in_val_msg call _print mov ecx, a call _get_input ;make 'a' an actual number rather than a char. sub dword [a], 0x30 mov edx, in_val_len mov ecx, in_val_msg call _print mov ecx, b call _get_input ;calc real number for 'b' sub dword [b], 0x30 mov eax, dword [a] mov ebx, dword [b] add eax, ebx ;get the character for our sum. add eax, 0x30 mov dword [sum], eax mov edx, out_val_len mov ecx, out_val_msg call _print mov [sum+1], dword 0xa mov edx, 4 mov ecx, sum call _print push 0x1 mov eax, 1 push eax int 0x80 ret

section .data in_val_msg db "Please input an integer:",0 in_val_len equ $-in_val_msg out_val_msg db "The sum of a+b is: ",0 out_val_len equ $-out_val_msg

section .bss a resd 1 b resd 1 sum resd 1 </lang> This will not work on numbers over 0(from 1 to 0). This is due to the fact, numbers higher than 0(10,11, etc) are in fact strings when taken from the keyboard. A much longer conversion code is required to loop through and treat each number in the string as separate numbers. For example, The number '10' would have to be treated as a 1 and a 0.

Yorick

<lang yorick>a = b = 0; read, a, b; write, a + b;</lang>