If you had done a search, you probably would have come up with
Padding Out Strings, although this discussion went a tad deeper then that one.
There are other uses for padding zeros than homework you know. Image frame numbers for instance - the padded zeros help OSs list the frames in the correct order. (speaking from experience, having written innumerable little scripts that do strange and wonderful things to a large number of frames)
-
dystrophy -