class Solution {
public:
    pair<int,int> expendaroundcenter(string& s,int left,int right)
    {
        while(left>=0 && right<s.size() && s[left] == s[right])
        {
            left--;
            right++;
        }

        return {left+1,right-1};
    }
    string longestPalindrome(string s) {
       int start = 0;
       int end = 0;
       for(int i=0;i<s.size()-1;i++)
       {
           auto [left1,right1] = expendaroundcenter(s,i,i);
           auto [left2,right2] = expendaroundcenter(s,i,i+1);

           if(right1 - left1 > end - start)
           {
               start = left1;
               end = right1;
           }
           if(right2 - left2 > end - start)
           {
               start = left2;
               end = right2;
           }
       } 
       return s.substr(start,end-start+1);
    }
};