LeetCode: Happy Number

Write an algorithm to determine if a number is "happy".

A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not include 1. Those numbers for which this process ends in 1 are happy numbers.

Example: 19 is a happy number

• 12 + 92 = 82
• 82 + 22 = 68
• 62 + 82 = 100
• 12 + 02 + 02 = 1

class Solution {public:    bool isHappy(int n) {        unordered_map<long, long> m_map;        while(1)        {            long happyNum = getHappy(n);            if(happyNum == 1 || happyNum == 0)                return true;            if(m_map.find(happyNum) != m_map.end())            {                return false;            }            else            {                m_map[n] = happyNum;                n = happyNum;            }        }    }private:    long getHappy(long n)    {        long result = 0;        while(n != 0)        {            int digit = n%10;            result += digit * digit;            n /= 10;        }        return result;    }};