C :

#include <stdio.h>
int main()
{
	int a,b;
	while(scanf("%d%d",&a,&b)!=EOF)
	{
		printf("%d\n",a+b);
	}
	return 0;
}

C++ :

#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
#ifndef ONLINE_JUDGE
	freopen("in.txt","r",stdin);
#endif
	int a,b;
	while(cin >>a >>b)
	{
		cout <<a+b <<endl;
	}
	return 0;
}

Pascal :

program abprob;
var
  a,b:longint;
begin
   readln(a,b);
   writeln(a+b);
end.

Java :

import java.util.*;
public class Main
{
	public static void main(String args[])
	{
		Scanner cin = new Scanner(System.in);
		int a,b;

		while(cin.hasNextInt())
		{
			a = cin.nextInt();
			b = cin.nextInt();
			System.out.println(a+b);
		}
	}
}

Bash :

read a b
let c=$a+$b
echo $c

Python :

#!/usr/bin/python2
a=raw_input() 
b=a.split(" ") 
print eval(b[0]+"+"+b[1]) 

C# :

using System;
class Program {
    public static void Main() {
        string line;
        string []p;
        int a,b;
        while((line=Console.ReadLine())!=null){
            p=line.Split(' ');
            a=int.Parse(p[0]);b=int.Parse(p[1]);
            Console.WriteLine(a+b);
        }
    }
}