in reply to
counter for each regex match.
However, I kept receiving use of uninitialized value $count error and a long string of numbers at the end as the result.
From your own description of the problem, the main point is to move the print statement outside of the while loop, so that it gets executed only once after you have finished looping on the input.
Initializing $count to 0 when you declare it is slightly less important, but it will avoid the "uninitialized value" warning in the case where nothing was matched in your while loop.