#include <iostream>

int main(){
    std::string S, T, _;
    int a, b;
    std::cin >> S >> a >> _;
    std::cin >> T >> b >> _;

    if(a == b){
        std::cout << -1 << std::endl;
    }else if(a > b){
        std::cout << S << std::endl;
    }else{
        std::cout << T << std::endl;
    }
}