count and say

https://leetcode.com/problems/count-and-say/

class Solution {
public:
    string countAndSay(int n) {
        if(n == 1)
        {
            return "1";
        }
        else if(n == 2)
        {
            return "11";
        }

        string oldstr = "11";
        string newstr;
        for(int i = 2; i<n; i++)
        {
            newstr.clear();
            //cout<<newstr<<endl;
            int count = 1;
            for(int j = 0; j<oldstr.length(); j++)
            {
                if(j == oldstr.length()-1 || oldstr[j+1] != oldstr[j])
                {
                    newstr = newstr + to_string(count);
                    newstr.push_back(oldstr[j]);
                    //cout<<count<<endl;
                    //cout<<newstr<<endl;
                    count = 1;
                }
                else
                {
                    count++;
                }
            }
            oldstr = newstr;
        }

        return newstr;
    }
};