#include <bits/stdc++.h>
using namespace std;
const int MXN = (int)1e6 + 10;
const int INF = (int)1e9 + 7;
const long long LINF = (long long)1e18 + 10;
const double EPS = (double)1e-9;
const double PI = (double)acos(-1.0);
string s;
int main() {
  cin >> s;
  string st = s;
  reverse(st.begin(), st.end());
  s += st;
  cout << s;
  return 0;
}
