#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using mint = modint998244353;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repf(i, n, flag) for (int i = 0; i < (int)(n) && flag; i++)
#define all(v) v.begin(), v.end()


bool is_pld(string s) {
    string t = s;
    reverse(all(t));
    return s == t;
}

int main() {
    string a;
    cin >> a;
    rep(i, a.size()) {
        string tmp = a.substr(0, i);
        reverse(all(tmp));
        if(is_pld(a + tmp)) {
            cout << a + tmp << endl;
            return 0;
        }
    }
}