#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
const int N = 1e2 + 2, oo = 2e9, md = 1e9 + 7;
int main() {
  ios::sync_with_stdio(false);
  cin.tie();
  string s, ss;
  cin >> s;
  ss = s;
  reverse(s.begin(), s.end());
  cout << s << ss;
  return 0;
}
