problem

​​202. Happy Number​​

 code

class Solution {
public:
    bool isHappy(int n) {
        while(n!=1 && n!=4)
        {
            int sum = 0;
            int tmp = n;
            while(tmp)
            {
                sum += pow(tmp%10, 2);//
                tmp = tmp / 10;//
            }
            n = sum;
        }
        return 1==n;
        
    }
};

1. ​​Leetcode_Happy Number​​;

2. ​​GrandYang_cnblogs​​;