Question

Question 1

Assume a function called count_primes is pre-definied. If consumes two int arguments start and stop that returns the number of prime integers between start (inclusive) and stop (exclusive). Note: The start value must be less than or equal to the stop value. Enter 3 assertEqual statements to test the count_primes function.

Question 2

Define a function called count_primes that consumes two int arguments start and stop that returns the number of prime integers between start (inclusive) and stop (exclusive). You may assume that start will be less than or equal to stop. You may use the pre-defined function called is_prime which consumes a positive number and returns True if the number is prime and False if the number is not prime.

Python language!

Answer 1

def is_prime(n):
    if n > 1:
        for i in range(2, n):
            if (n % i) == 0:
                return False
    return n > 1


def count_primes(start, stop):
    count = 0
    for i in range(start, stop):
        if is_prime(i):
            count += 1
    return count


assert count_primes(1, 5) == 2
assert count_primes(2, 6) == 3
assert count_primes(2, 2) == 0