Write a program to check whether a given number is an ugly number.
Ugly numbers are positive numbers whose prime factors only include 2, 3, 5.
Example 1:
Input: 6 Output: true Explanation: 6 = 2 × 3
Example 2:
Input: 8 Output: true Explanation: 8 = 2 × 2 × 2
Example 3:
Input: 14 Output: false Explanation:14is not ugly since it includes another prime factor7.
Note:
1 is typically treated as an ugly number.struct Solution;
impl Solution {
fn is_ugly(mut num: i32) -> bool {
if num < 1 {
return false;
}
while num % 2 == 0 {
num /= 2;
}
while num % 3 == 0 {
num /= 3;
}
while num % 5 == 0 {
num /= 5;
}
num == 1
}
}
#[test]
fn test() {
assert_eq!(Solution::is_ugly(6), true);
assert_eq!(Solution::is_ugly(8), true);
assert_eq!(Solution::is_ugly(14), false);
}