#include <bits/stdc++.h>
using namespace std;
int main() {
  string s, s1;
  while (cin >> s) {
    int l = s.length();
    for (int i = l - 1; i >= 0; i--) {
      s1 += s[i];
    }
    cout << s + s1 << endl;
  }
}
