#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 100;
int dp[N];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  string s;
  cin >> s;
  cout << s;
  reverse((s).begin(), (s).end());
  cout << s;
  return 0;
}
