You seem to be asking a lot of questions that are pretty much the same as the other ones. You should really read up on some more tutorials. Considering what you've done in the programs in your previous posts, the program you have wrote above should almost look english to you. "while ( a is not equal to 5)"
if a != 5 it will loop forever. Figure out a way which asks the user to enter another number (assuming you want to wait until the user enters 5) in the while loop.