#include <bits/stdc++.h>
using namespace std;
string reverse(string s) {
  string s1 = "";
  for (int i = s.size() - 1; i >= 0; i--) {
    s1 += s[i];
  }
  return s1;
}
int main() {
  string s;
  cin >> s;
  cout << s + reverse(s);
}
