Problem Statement

A+B   ─── a classic problem in programming contests,   it's given so contestants can gain familiarity with the online judging system being used.

Given two integers,   A and B. Their sum needs to be calculated.

Two integers are written in the input stream, separated by space(s):

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

Let's start with the solution:

#!/bin/sh
read a b || exit
echo `expr "$a" + "$b"`

#!/bin/bash
read a b || exit
echo $(( a + b ))

echo 2 3 | ksh a+b.sh
5

a=0;b=0;read a;read b;echo "Sum of $a and $b is "$((a+b))

set line=$<
set input=($line)
@ sum = $input[1] + $input[2]
echo $sum