202 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) {
        set<int> visit;
        
        while(true)
        {
            if(n == 1)
                return true;
                
            vector<int> iVec;
            while(n)
            {
                iVec.push_back(n % 10);
                n /= 10;
            }
            
            for(int i = 0;i < iVec.size();++i)
                n = n + iVec[i] * iVec[i];
                
            if(visit.find(n) != visit.end())
                return false;
                
            visit.insert(n);
        }
    }
};