#include <bits/stdc++.h>
using namespace std;
const int C = 202020;
string s, t;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> s;
  t = s;
  reverse(t.begin(), t.end());
  cout << s + t;
  return 0;
}
