丑数

public class Solution {
    /*
     * @param num: An integer
     * @return: true if num is an ugly number or false
     */
    public boolean isUgly(int num) {
        if (num == 1)
            return true;
        
        while (num >= 2 && num % 2 == 0) num /= 2;
        while (num >= 3 && num % 3 == 0) num /= 3;
        while (num >= 5 && num % 5 == 0) num /= 5;
        
        return num == 1;
    }
}