#include <bits/stdc++.h>
using namespace std;
bool IsPalindrome(string s) {
  for (int i = 0; i <= s.size(); i++) {
    if (s[i] != s[s.size() - 1 - i]) return false;
  }
  return true;
}
string palindromSupersequence(string s) {
  if (IsPalindrome(s)) return s;
  for (int i = s.size() - 2; i >= 0; i--) s = s + s[i];
  return s;
}
int main() {
  string s;
  cin >> s;
  cout << palindromSupersequence(s);
}
