#include <bits/stdc++.h>
const double EPS = (1e-7);
int dcmp(double x, double y) { return fabs(x - y) <= EPS ? 0 : x < y ? -1 : 1; }
using namespace std;
int main() {
  string num;
  cin >> num;
  int n = num.length();
  vector<int> vec(n * 2 + 1);
  for (int i = 0; i < n; ++i) {
    vec[i] = num[i] - '0';
    vec[(n * 2) - i - 1] = num[i] - '0';
  }
  for (int i = 0; i < n * 2; ++i) {
    cout << vec[i];
  }
}
