#include <iostream>		//cin, cout
#include <vector>		//vector
#include <algorithm>	//sort,min,max,count
#include <string>		//string,getline, to_string
#include <cstdlib>		//abs(int)
#include <utility>		//swap, pair
#include <deque>		//deque
#include <climits>		//INT_MAX
#include <bitset>		//bitset
#include <cmath>		//sqrt, ceil. M_PI, pow, sin
#include <ios>			//fixed
#include <iomanip>		//setprecision

using namespace std;

int main() {

	char a[6];
	char temp;

	for (int i = 0; i < 6; i++) {
		cin.get(a[i]);
		cin.get(temp);
	}


	if (a[3] < a[0]) {
		cout << "YES" << endl;
	}
	else if (a[3] > a[0]) {
		cout << "NO" << endl;
	}
	else {
		if (a[4] < a[1]) {
			cout << "YES" << endl;
		}
		else if (a[4] > a[1]) {
			cout << "NO" << endl;
		}
		else {
			if (a[5] <= a[2]) {
				cout << "YES" << endl;
			}
			else {
				cout << "NO" << endl;
			}
		}
	}

	return 0;

}