LeetCode Ugly Number

Description

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.

The original problem is here.

The original code is here.

My Solution

I solve this problem in C++, as below:

/*
*Ugly Number
*Author: shuaijiang
*Email: zhaoshuaijiang8@gmail.com
*/
#include<iostream>
#include<stdlib.h>
using namespace std;

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

int main(){
    Solution s;
    int num = 14;
    bool result = s.isUgly(num);
    cout<<"Result="<<result<<endl;
    system("pause");
    return 0;
}

Note

Recursion is used to the problem.