#include<iostream>
#include<algorithm>
#include<string>

using namespace std;

void solve1(){
	string a, b;
	string Pa, Pb;
	string Xa, Xb;
	cin >> a >> Pa >> Xa;
	cin >> b >> Pb >> Xb;

	
	if (Pa.size() > Pb.size()){
		cout << a;
		return;
	}
	else if (Pb.size() > Pa.size()){
		cout << b;
		return;
	}
	else if (Pa.size() == Pb.size()){

		for (int i = 0; i < Pa.size(); i++)
		{
			if (Pa[i] > Pb[i])
			{
				cout << a;
				return;
			}
			else if (Pa[i]<Pb[i])
			{
				
				cout << b;
				return;
			}
		}
		cout << "-1" << endl;
	}

}


int main(){
	solve1();
	return 0;
}