#include <bits/stdc++.h>
using namespace std;
const int inf = INT_MAX;
const long long int infl = LLONG_MAX;
int main() {
  std::ios::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL);
  string s;
  cin >> s;
  cout << s;
  int n = s.length();
  for (int i = n - 1; i >= 0; i--) {
    cout << s[i];
  }
  cout << endl;
  return 0;
}
