[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.

思路：找到丑数（因子只含2、3、5），判断是否能被2、3、5整除，可以的话递归判断因子

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