func_code_string: #include <bits/stdc++.h>   using namespace std;   const double PI = 3.141592653589793238;   const double E = 2.718281828459045235;   const int MOD = 1000000007;   const long long INF = 1000000000;   int main() {     ios_base::sync_with_stdio(0);     string s;     cin >> s;     cout << s;     reverse((s).begin(), (s).end());     cout << s;     return 0;   }   