Write a program that counts number of prime numbers in an Array. The program must be able to use functions, in particular, The program must use the count as reference variable in main.
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I thought @Thomas1965's code snippet was a good starting point for you (although there is an error in it--you'll have to discover it before you can ask questions about it). My recommendation for you, however, is to not worry about count_primes until you get is_prime working first. Test is_prime on a series of numbers and make sure it works before worrying about dealing with an array.
Get out there and try stuff and see what it does. When it doesn't work, ask us a question.