#include <bits/stdc++.h>
using namespace std;
const long long mod = 1e9 + 7;
const long long inf = (1ll << 62);
const int MX = 3e5 + 9;
string s;
bool vis[MX];
int main() {
  cin >> s;
  cout << s;
  reverse(s.begin(), s.end());
  cout << s << endl;
}
