#include "bits/stdc++.h"

using namespace std;
using ll = long long;
const double pi = acos(-1);
#define FOR(i,a,b) for (ll i=(a),__last_##i=(b);i<__last_##i;i++)
#define RFOR(i,a,b) for (ll i=(b)-1,__last_##i=(a);i>=__last_##i;i--)
#define REP(i,n) FOR(i,0,n)
#define RREP(i,n) RFOR(i,0,n)
#define __GET_MACRO3(_1, _2, _3, NAME, ...) NAME
#define rep(...) __GET_MACRO3(__VA_ARGS__, FOR, REP)(__VA_ARGS__)
#define rrep(...) __GET_MACRO3(__VA_ARGS__, RFOR, RREP)(__VA_ARGS__)
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v) {
	REP(i, v.size()) { if (i)os << " "; os << v[i]; }return os;
}
template<typename T> ostream& operator<<(ostream& os, const vector<vector<T>>& v) {
	REP(i, v.size()) { if (i)os << endl; os << v[i]; }return os;
}

const ll INF = 1LL << 60;
ll MOD = 1000000007;
ll _MOD = 1000000009;
double EPS = 1e-10;

int main() {
	string s1, a, ss1, s2, b, ss2;

	cin >> s1 >> a >> ss1 >> s2 >> b >> ss2;

	if (a.size() > b.size()) {
		cout << s1 << endl;
	}
	else if (a.size() < b.size()) {
		cout << s2 << endl;
	}
	else {
		REP(i, a.size()) {
			if (a[i] - '0' > b[i] - '0') {
				cout << s1 << endl;
				return 0;
			}
			else if (a[i] - '0' < b[i] - '0') {
				cout << s2 << endl;
				return 0;
			}
		}
		cout << -1 << endl;
	}
}