#include <bits/stdc++.h>
using namespace std;
int main() {
  char A[2050], B[1005];
  int i, j, l, k = -1;
  cin >> A;
  l = strlen(A);
  for (i = l - 1; i >= 0; i--) {
    k++;
    B[k] = A[i];
  }
  strcat(A, B);
  A[2 * l] = '\0';
  cout << A;
}
