#include <bits/stdc++.h>
using namespace std;
int main() {
  string n;
  int x;
  cin >> n;
  string s;
  for (int i = n.size() - 1; i >= 0; --i) {
    s += n[i];
    s = n[i] + s;
  }
  cout << s << "\n";
}
