13. Prime Pairs

import math

first_start = int(input())
second_start = int(input())
first_diff = int(input())
second_diff = int(input())

for i in range(first_start, first_start + first_diff + 1):
    for j in range(second_start, second_start + second_diff + 1):
        is_first_prime = True
        is_second_prime = True

        for k in range(2, int(math.sqrt(i)) + 1):
            if i % k == 0:
                is_first_prime = False
                break
        for k in range(2, int(math.sqrt(j)) + 1):
            if j % k == 0:
                is_second_prime = False
                break
        if is_first_prime and is_second_prime:
            print(f'{i}{j}')