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.

class Solution {
    public boolean isUgly(int num) {
        if(num == 0) return false;
        if(num == 1) return true;

        while(num % 2 == 0) num = num / 2;
        while(num % 3 == 0) num = num / 3;
        while(num % 5 == 0) num = num / 5;

        if(num == 1) return true;
        return false;
    }
}