I have already enroled five finger prints stored in the scanner with ID's 1,2,3,4 and 5.
Completely irrelevant.
In my program i can declare an array to hold a copy of the ID's.
Why is that important? What, EXACTLY, do you get when you scan a fingerprint?
initialise a counter maybe to 0.
int scanCount = 0;
You write the rest.