#include <iostream>
#include <algorithm>
#include <string>
using namespace std;
class Solution {
public:
    string longestPalindrome(string s) {
        string result;

        int max = 0;
        for(int i = 1; i< s.size()-1; i++) {

            if ( s.at(i-1)==s.at(i+1) ) {
                string value = Palindrome(s, i-1, i+1);
                if (max < static_cast<int>(value.size()) ) {
                    result = value;
                    max = value.size();
                }
            }

            if( s.at(i-1) == s.at(i) ) {
                string value = Palindrome(s, i-1, i);
                if (max < static_cast<int>(value.size()) ) {
                    result = value;
                    max = value.size();
                }
            }

            if( s.at(i) == s.at(i+1) ) {
                string value = Palindrome(s, i, i+1);
                if (max < static_cast<int>(value.size()) ) {
                    result = value;
                    max = value.size();
                }
            }

        }
        return result;
    }
    string Palindrome(string s, int left, int right) {
        int min_size = std::min(left, static_cast<int>(s.size()-(right+1)));
        for (int i=0; i<=min_size; i++ ) {
            if (s.at(left) == s.at(right)) {
                left--;
                right++;
            }
            else break;
        }
        left++;

        string_view total = s.substr(left, right-left);

        return string(total);
    }
};

int main()
{
    Solution sol;
    string s;
    {
        s = "AbAaaSTRoRTSaaF";
        cout << sol.longestPalindrome(s) << endl;
    }
    {
        s = "babad";
        cout << sol.longestPalindrome(s) << endl;
    }
    {
        s = "cbbd";
        cout << sol.longestPalindrome(s) << endl;
    }
    {
        s = "cbdd";
        cout << sol.longestPalindrome(s) << endl;
    }
    return 0;
}