#include <bits/stdc++.h>
using namespace std;
long long a, b, c, d, k, n, m, x, y, z, cnt, ans, tt;
char f[1001][1001], h[1001];
vector<int> v, q, t;
string s, g, r;
int main() {
  cin >> s;
  g = s;
  reverse(g.begin(), g.end());
  if (s == g)
    cout << s;
  else {
    cout << s << g;
  }
}
