Shell script to Create a calculator by case system

SOURCE CODE:

echo “Enter the values :”

echo “x:”

read x

echo “y:”

read y

echo “1: Addition”

echo “2: Subtraction”

echo “3: multiplication.”

echo “4: Division.”

echo “Enter the choice:”

read c

case “$c” in

ans =`expr $x + $y`;;

2)   ans =`expr $x - $y`;;

ans =`expr $x \ *y`;;

if [ $y != 0]

then

           ans =`expr $x / $y`;;

else

     echo “Invalid operation”

fi;;

esac

echo “Ans:“ $ans

OUTPUT: 

Enter the values :

X:

1

Y:

3

1: Addition

2: Subtraction

3: multiplication

4: Division

Enter the choice:

3

Ans:3