[pbloraneFH]

It's just a script but easy to solve

copy the script to web challenge and run with python

input_line = input()


def is_prime(n):
    if n < 2:
        return False
    if n == 2:
        return True
    if n % 2 == 0:
        return False
    for i in range(3, int(n ** 0.5) + 1, 2):
        if n % i == 0:
            return False
    return True


numbers = map(int, input_line.strip().split())


product = 1
for number in numbers:
    if is_prime(number):
        product *= number


print(product)