https://www.acmicpc.net/problem/15520 15520번: Prime-Factor Prime A positive integer is called a "prime-factor prime" when the number of its prime factors is prime. For example, 12 is a prime-factor prime because the number of prime factors of 12 = 2 × 2 × 3 is 3, which is prime. On the other hand, 210 is not a prime-f www.acmicpc.net [사용한 것] 에라토스테네스의 체 1. 나누려는 소수 \(i\)의 범위 정하기 어떤 수가 소수인지 확인하는 방법..