[Leetcode 263] 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.

solution: according to defination, only be divided by 2,3,5

public boolean isUgly(int num) {
        if(num<=0) return false;
        while(num%2 == 0){
            num = num/2; 
        }
        while(num%3 == 0){
            num = num/3;
        }
        while(num%5 == 0){
            num = num/5;
        }
        return num == 1;
    }