#include <bits/stdc++.h>
const long long maxn = 1e5 + 123, inf = 1e9, INF = 1e18, N = 1e6,
                mod = 95542721;
using namespace std;
string second;
int main() {
  cin >> second;
  for (int i = 0; i < second.size(); i++) cout << second[second.size() - 1 - i];
  cout << second;
}
