#include <bits/stdc++.h>
using namespace std;
long long sum, num, maxi = -10e9, maxn = -10e9, mini = 10e9, minn = 10e9;
string n;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie();
  cout.tie();
  cin >> n;
  cout << n;
  for (int i = n.size() - 1; i >= 0; i--) {
    cout << n[i];
  }
  return 0;
}
