#include <bits/stdc++.h>
using namespace std;
void c_p_c() {}
void solution() {
  string s;
  cin >> s;
  string ans = s;
  for (int i = s.length() - 1; i >= 0; i--) {
    ans += s[i];
  }
  cout << ans << endl;
}
int32_t main() {
  c_p_c();
  solution();
  return 0;
}
