#!/bin/bash

read a b c

if [ "$b" == '+' ]
then
    x=$(($a+$c))
    echo $x
elif [ "$b" == '-' ]
then
    x=$(($a-$c))
    echo $x

elif [ "$b" == '*' ]
then
    x=$(($a*$c))
    echo $x
elif [ "$b" == '/' ]
then
    echo DIVISION  $a  by  $c
    x=`expr $a / $c`
    echo $x
else
    echo "$b" is not a legal operation
fi