LeetCode: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.

Credits:

Special thanks to @jianchao.li.fighter for adding this problem and creating all test cases.

想了好久丑数说什么，又想了好久丑数怎么算。写出来后一直提示超时，想怎么优化这个程序但是怎么也想不出来，特别纳闷，这该是最快的了啊，结果仔细看了下，停在输入0上面，原来如此。。。加上了class Solution {
public:
bool isUgly(int num) {
if (num == 0) {
return false;
}
while(num % 2 == 0)
num /= 2;
while(num % 3 == 0)
num /= 3;
while(num % 5 == 0)
num /= 5;
return (num == 1) ? true : false;
}
};


对0的判断，通过