#include <bits/stdc++.h>
using namespace std;
vector<int> arr;
int main() {
  cin.tie(nullptr);
  ios_base::sync_with_stdio(false);
  string s;
  cin >> s;
  int sz = s.size();
  string stri = "";
  for (int i = sz - 1; i >= 0; --i) {
    stri += s[i];
  }
  string str = s + stri;
  cout << str;
  return 0;
}
