#include <bits/stdc++.h>
using namespace std;
int main() {
  string s, ans, s1;
  cin >> s;
  s1 = s;
  int l = s.length(), i;
  int j = l - 1, flag = 0;
  while (i < j) {
    if (s[i] != s[j]) {
      flag = 1;
      break;
    }
    i++;
    j--;
  }
  if (flag) {
    reverse(s1.begin(), s1.end());
    ans = s + s1;
    cout << ans;
  } else
    cout << s;
  return 0;
}
