In the lessons we learned about conditionals and control flow, and the number of ways that we can direct traffic based on satisfying certain conditions or states.
In your problem, the first state, as it were, is a string return value that looks like a number but that we cannot use in arithmetic. So we arbitrarily alter its state to a type of data that is suitable for doing math, a number, and in this case, an integer.
The next state we need to check is the actual value of the number. We need to be able to carry out different actions depending upon that number. What did you learn in the unit that will guide you through this process?