#include <bits/stdc++.h>
using namespace std;
int main() {
  string n;
  cin >> n;
  cout << n;
  long long int m = n.length();
  char arr[m];
  for (long long int i = 0; i < m; i++) {
    arr[i] = n[m - i - 1];
  }
  for (long long int i = 0; i < m; i++) cout << arr[i];
  return 0;
}
