#include <bits/stdc++.h>
using namespace std;
const int inf = 1e9;
const double eps = 1e-9;
const long double pi = acos(-1);
const int nmax = 2010;
const long long mod = 1e4;
int main() {
  string s;
  cin >> s;
  string s1 = s;
  reverse(s.begin(), s.end());
  cout << s1 << s << endl;
}
