#include <bits/stdc++.h>
using namespace std;
const int mod = 1e9 + 7;
const long long int INF = 1e17;
int main() {
  ios_base::sync_with_stdio(0);
  long long int i, j, k, l;
  string s;
  cin >> s;
  string s1 = s;
  reverse(s1.begin(), s1.end());
  cout << s + s1 << endl;
  return 0;
}
