#include <bits/stdc++.h>
using namespace std;
int main()
{
    string sa, sb, pa, pb, ans = "-1";
    char c;
    cin >> sa >> pa >> c >> sb >> pb >> c;
    
    if (pa.length() > pb.length()) ans = sa;
    else if (pa.length() == pb.length()) {
        int i = 0;
        while (i < pa.length()) {
            if (pa[i] > pb[i]) {
                ans = sa;
                break;
            } else if (pa[i] < pb[i]) {
                ans = sb;
                break;
            }
            i++;
        }
    }
    else ans = sb;
    cout << ans << endl;
    return 0;
}