#include<iostream>
#include<algorithm>
using namespace std;
string L,R;
int N;
main()
{
    cin>>N;
    for(;N--;)
    {
        int i;char c;cin>>i>>c;
        (i?L:R)+=c;
    }
    reverse(L.begin(),L.end());
    cout<<L+R<<endl;
}