[leetcode] Ugly Number

from : https://leetcode.com/problems/ugly-number/
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

.
For example,

6, 8

are ugly while

14

is
not ugly since it includes another prime factor

7

.

Note that

1

is typically treated as an ugly number.

class Solution {
public:
bool isUgly(int num) {
if(1 >= num) return 1 == num;

while(num >= 2 && 0 == (num&1)) num >>= 1;
while(num >= 3 && 0 == num%3) num /= 3;
while(num >= 5 && 0 == num%5) num /= 5;
return 1 == num;
}
};