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.

public class Solution {
    public boolean isUgly(int num) {
        if(num==0) return false;
        boolean flag = true;
        while(flag) {
            flag = false;
            if(num%2==0) {
                num = num/2;
                flag = true;
            }
            else if(num%3==0) {
                num = num/3;
                flag = true;
            }
            else if(num%5==0) {
                num = num/5;
                flag = true;
            }
        }
        if(num==1) return true;
        else return false;
    }
}