#include<iostream>
#include<string>
#include<fstream>
#include<iomanip>
#include<vector>
#include<cctype>
#include<algorithm>
#include<sstream>
using namespace std;

int main()
{
	int a[3], b[3];
	char d;
	string s, t;
	stringstream ss;
	cin >> a[0] >> d >> a[1] >> d >> a[2];
	cin >> b[0] >> d >> b[1] >> d >> b[2];
	for (int i = 0; i < 3; i++)
	{
		string p, q;
		ss << a[i]; ss >> p; ss.clear();
		s += p;
		ss << b[i]; ss >> q; ss.clear();
		t += q;
		p.clear();
		q.clear();
	}
	if (s >= t)cout << "YES" << endl;
	else cout << "NO" << endl;
	return 0;
}