#include<bits/stdc++.h>
using namespace std;
#include<atcoder/all>
using namespace atcoder;
using ll = long long;
string s;
bool isp(string s){
	string t = s;
	reverse(t.begin(),t.end());
	return t==s;
}

void solve(){
	int n = s.size();
	for(int i = 0;i<=n;i++){
		if(isp(s)){
			cout<<s<<endl;
			return;
		}
		s.insert(s.begin()+n,s[i]);
	}
}

signed main(){
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	cin >> s;
	solve();
}