A+B
You are encouraged to solve this task according to the task description, using any language you may know.
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.
- Output data
- The required output is one integer: the sum of A and B.
- Example:
Input Output 2 2 4 3 2 5
Ada
<lang Ada>-- Standard I/O Streams
with Ada.Integer_Text_Io; procedure APlusB is
A, B : Integer;
begin
Ada.Integer_Text_Io.Get (Item => A); Ada.Integer_Text_Io.Get (Item => B); Ada.Integer_Text_Io.Put (A+B);
end APlusB; </lang>
ALGOL 68
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
<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>
AWK
<lang awk> {print $1 + $2} </lang>
Batch File
<lang dos>::aplusb.cmd @echo off setlocal set /p a="A: " set /p b="B: " set /a c=a+b echo %c% endlocal </lang>
BASIC
<lang qbasic>DEFINT A-Z
tryagain: backhere = CSRLIN INPUT "", i$ 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
<lang befunge>&&+.@</lang>
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>
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>: 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>
Haskell
<lang haskell>sum' :: [Char] -> Int sum' = sum . map read . words
main = getLine >>= (\xs -> print $ sum' xs)</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
In the following line, (1!:1) 3 reads a line from STDIN; _1}. drops the last newline character; ;.0 then cuts it into "words", each of which are converted into a number (by ". when applied with ;.), resulting in a vector which is then reduced with addition using +/, producing the result. <lang J>+/".;.0 (_1}.(1!:1) 3)</lang> Here's a little script, called "a+b.ijs": <lang J>#!/Applications/j602/bin/jconsole echo +/".;.0 (_1}.(1!:1) 3) 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
<lang html4strict><html> <body>
<script type='text/javascript'>
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>
Logo
<lang logo>show apply "sum readlist</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($)}} end
in
{Show {ReadInt}+{ReadInt}}</lang>
Pascal
<lang pascal>var
a, b: integer;
begin
readln(a, b); writeln(a + b);
end.</lang> Same with input from file input.txt and output from file output.txt. <lang pascal>var
a, b: integer;
begin
reset(input, 'input.txt'); rewrite(output, 'output.txt'); readln(a, b); writeln(a + b); close(input); close(output);
end.</lang>
Perl
<lang Perl>my ($a,$b) = split(/\D+/,<STDIN>); print "$a $b " . ($a + $b) . "\n";</lang>
PicoLisp
<lang PicoLisp>(+ (read) (read)) 3 4 -> 7</lang>
PureBasic
Console
<lang PureBasic>x$=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$,2," ")) If OpenFile(1,"out.txt") WriteString(1,str(a+b)) CloseFile(1) EndIf CloseFile(0)
EndIf </lang>
Python
Console
<lang python>r = raw_input().split() print int(r[0]) + int(r[1])</lang>
File
<lang python>fin = open("input.txt", "r") fout = open("output.txt","w") r = fin.readline().split() fout.write(str(int(r[0]) + int(r[1])))</lang>
Ruby
<lang ruby>puts gets.split.map{|x| x.to_i}.inject{|sum, x| sum + x}</lang>
<lang ruby>puts gets.split.map(&:to_i).inject(&:+)</lang>
Scala
<lang scala>println(readLine() split " " take 2 map (_.toInt) sum)</lang>
Scheme
<lang scheme>(write (+ (read) (read)))</lang>
SNOBOL4
Simple-minded solution (literally "two somethings separated by space") <lang snobol> input break(" ") . a " " rem . b output = a + b end</lang>
"Integer aware" solution: <lang snobol> nums = "0123456789" input span(nums) . a break(nums) span(nums) . b output = a + b end</lang>
Tcl
<lang tcl>scan [gets stdin] "%d %d" x y puts [expr {$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>