[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.

如果可以被2，3，5整除一直除下去，到不能除为止，如果是丑数最后的num就是1.

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