#include <bits/stdc++.h>
using namespace std;
const long long INF = 1LL << 50LL;
const double PI = 3.14159265358979323846264;
int main() {
  string s;
  cin >> s;
  string rs = s;
  reverse(rs.begin(), rs.end());
  cout << s << rs << endl;
  return 0;
}
