#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, n) for (int i = 0; i < (ll)(n); i++)
#define oke cout << "Yes" << '\n';
#define dame cout << "No" << '\n';
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
using HaiI = vector<vector<int>>;
using Hai2 = vector<vector<ll>>;
using HaiB = vector<vector<bool>>;
using Hai3 = vector<vector<vector<ll>>>;

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	cout << fixed << setprecision(15);
	string N;
	cin>>N;
	cout<<N+N;
}