#include <iostream>
#include <string>

using namespace std;
int main() 
{
	string r;
	int N;
	cin >> N;
	for (int i = 0; i < N; ++i)
	{
		int T;
		string S;
		cin >> T, S;
		if (T == 0)
			r += S;
		else
			r = S + r;
	}
	cout << r << endl;
	return 0;
}