#include<iostream>
#include<algorithm>
#include <vector>
#include<cmath>
#include<iomanip>
using namespace std;
typedef long long int lont;
int main() {
	vector<char>veca(10);
	for (int ia = 0; ia < 10; ia++) {
		cin >> veca.at(ia);
	}
	vector<int>vecb(6);
	vecb.at(0) = veca.at(0) - '0';
	vecb.at(1) = veca.at(2) - '0';
	vecb.at(2) = veca.at(4) - '0';
	vecb.at(3) = veca.at(5) - '0';
	vecb.at(4) = veca.at(7) - '0';
	vecb.at(5) = veca.at(9) - '0';

	if (vecb.at(0) < vecb.at(3)) {
		cout << "NO" << endl;
	}
	else if (vecb.at(0) > vecb.at(3)) {
		cout << "YES" << endl;
	}
	else {
		if (vecb.at(1) < vecb.at(4)) {
			cout << "NO" << endl;
		}
		else if (vecb.at(1) > vecb.at(4)) {
			cout << "YES" << endl;
		}
		else {
			if (vecb.at(2) < vecb.at(5)) {
				cout << "NO" << endl;
			}
			else if (vecb.at(2) > vecb.at(5)) {
				cout << "YES" << endl;
			}
			else {
				cout << "YES" << endl;
			}
		}
	}
}