Non Numeric Inputs

[eloy1073]

How should I code my program to recognize inputs that are not numeric.
Whenever a user inputs a letter in my code the code starts repeating infinitely.
I know I should probably use an if or else statement but I cant seem to get anything to work. If somebody could get back to me I would greatly appreciate it.

[TarikNeaj]

http://stackoverflow.com/questions/18728754/checking-input-value-is-an-integer