#include <iostream>
#include <string>
#include <vector>
#include <functional>
#include <algorithm>

#define REP(i,n) for(int i;i<(n);i++)

using namespace std;

int main() {
   // cin.tie(0);
   // ios::sync_with_stdio(false);

    string a, ap, b, bp, g;
    cin >> a >> ap >> g >> b >> bp >> g;
    if (ap.length() > bp.length())
        cout << a;
    else if (ap.length() < bp.length())
        cout << b;
    else {
        if (ap > bp)
            cout << a;
        else if (ap < bp)
            cout << b;
        else
            cout << -1;
    }
    cout << endl;

    return 0;
}