#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 100005;
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  string s;
  cin >> s;
  string t = s;
  reverse((t).begin(), (t).end());
  cout << s + t << "\n";
  return 0;
}
