#include <bits/stdc++.h>
using namespace std;
double PI = 3.14159265358979323843;
void Timo() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
}
void print(int n) {
  if (n == 0) {
    return;
  }
  print(n - 1);
  cout << "Hello world" << endl;
  print(n - 1);
}
int main() {
  Timo();
  string s;
  cin >> s;
  cout << s;
  reverse(s.begin(), s.end());
  cout << s << endl;
  return 0;
}
