#include <bits/stdc++.h>
using namespace std;
int main() {
  long long n, m, x = 1, y = 2;
  string a, b, c;
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  cin >> a;
  for (int i = a.size() - 1; i >= 0; i--) {
    b += a[i];
  }
  if (a == b)
    (cout << a);
  else
    cout << a << b;
}
