Assignment task: Whole Number Calculator
In this project you are to write a script that will ask the user for a whole number, and then ask the user for another whole number and then ask the user to select an operation (a add, s subtract, d divide, m multiply). The script will check if a whole number was entered or a non-number (like a letter) (we will not check for floats or doubles like 3.2 Linux doesn't do well with those). We will check that the user entered the correct letter for the operator (operator will be set to lowercase so if user enters "A" it will be changed to "a" in the script you can use the tr command for this it is in your book)