#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 c;
	cin >> a[0] >> c >> a[1] >> c >> a[2];
	cin >> b[0] >> c >> b[1] >> c >> b[2];
	for (int i = 0; i < 3; i++)
	{
		if (a[i] == b[i])continue;
		else if (a[i]>b[i])
		{
			cout << "YES" << endl;
			return 0;
		}
		else
		{
			cout << "NO" << endl;
			return 0;
		}
	}
	cout << "YES" << endl;
	return 0;
}