Thank you for your help firstly. I will use the tags in future. I use a numerical methods in C++ book dated from 1999. I am also restricted to using a Borland C++ edit program and haven't learnt to use anything else yet. Very, very new to this. It's not that easy, making your help greatly appreciated.

So this means I can stick any logic statement (not sure if that's what it is) in the for loop. Would a while loop do something similar?