#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll myRand(ll B) {
    return (ull) rng() % B;
}

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    string s; cin >> s;
    auto res = s+s;
    int n = s.size();
    for (int i = n-1; i >= 0; --i) {
        {
            int l = i, r = n-1-i;
            if(l < r) break;

            bool ok = true;
            for (int j = 1; j+i < n; ++j) {
                if(s[i+j] != s[i-j]) {
                    ok = false; break;
                }
            }
            if(ok) {
                res = s;
                for (int j = 1; i-j >= 0; ++j) {
                    if(i+j < n) continue;
                    res += s[i-j];
                }
            }
        }
        {
            int l = i, r = n-i;
            if(l < r) break;
            bool ok = true;
            for (int j = 0; j+i < n; ++j) {
                if(s[i+j-1] != s[i-j]) {
                    ok = false; break;
                }
            }
            if(ok) {
                res = s;
                for (int j = 1; i-j >= 0; ++j) {
                    if(i+j-1 < n) continue;
                    res += s[i-j];
                }
            }
        }
    }
    cout << res << endl;
}