#include <bits/stdc++.h>
using namespace std;

#ifdef _RUTHEN
#include <debug.hpp>
#else
#define show(...) true
#endif

using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); i++)
template <class T> using V = vector<T>;

bool is_palindrome(std::string &s) {
    int n = (int)s.size();
    for (int i = 0; i < n / 2; i++) {
        if (s[i] != s[n - 1 - i]) {
            return false;
        }
    }
    return true;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    string A;
    cin >> A;
    int N = (int)A.size();
    while (true) {
        string B(N, 'a');
        rep(i, A.size()) B[i] = A[i];
        for (int i = N - 1; i >= 0 and N - 1 - i < (int)A.size(); i--) B[i] = A[N - 1 - i];
        if (B.substr(0, (int)A.size()) == A and is_palindrome(B)) {
            cout << B << '\n';
            break;
        }
        N++;
    }
    return 0;
}