#include <bits/stdc++.h>
using namespace std;
long long digit(long long n) {
  long long temp = n;
  long long count = 0;
  while (temp) {
    temp = temp / 10;
    count++;
  }
  return count;
}
long long pow(int n) {
  long long num;
  long long st = 0;
  for (int i = 0; i < n; i++) {
    st = st * 10 + 9;
  }
  return st;
}
int main() {
  ;
  string n;
  cin >> n;
  cout << n;
  for (int i = 0; i < n.length(); i++) cout << n[n.length() - 1 - i];
  return 0;
}
