#include <bits/stdc++.h>
using namespace std;
string helper(const string& firstHalf) {
  string ans = "";
  for (int i = firstHalf.size() - 1; i >= 0; i--) ans += firstHalf[i];
  return ans;
}
int main() {
  string firstHalf;
  cin >> firstHalf;
  string secondHalf = helper(firstHalf);
  cout << firstHalf + secondHalf << endl;
  return 0;
}
