Given an integer n
, return true
if n
has exactly three positive divisors. Otherwise, return false
.
An integer m
is a divisor of n
if there exists an integer k
such that n = k * m
.
Input: n = 2 Output: false Explanation: 2 has only two divisors: 1 and 2.
Input: n = 4 Output: true Explanation: 4 has three divisors: 1, 2, and 4.
1 <= n <= 104
impl Solution {
pub fn is_three(n: i32) -> bool {
(1..=n).filter(|m| n % m == 0).count() == 3
}
}