#include <bits/stdc++.h>
using namespace std;
const double PI =
    3.14159265358979323846264338327950288419716939937510582097494459230;
struct debugger {
  static void call(const char *arg) {}
  template <typename T, typename... aT>
  static void call(const char *it, T a, aT... rest) {
    string b;
    for (; *it && (*it) != ','; it++) {
      b += *it;
    }
    cerr << b << " = " << a << " ";
    call(++it, rest...);
  }
};
int main() {
  string a, b;
  cin >> a;
  b = a;
  reverse(a.begin(), a.end());
  b += a;
  cout << b;
}
