#include <bits/stdc++.h>
using namespace std;
int main() {
  string s, ans = "";
  cin >> s;
  int i = 0, j = s.size() - 1;
  while (i < j) {
    if (s[i] == s[j]) {
      i++;
      j--;
      continue;
    } else {
      s.insert(s.begin() + j + 1, s[i]);
      i++;
    }
  }
  cout << s << endl;
}
