#include <iostream>
#include <string>
using namespace std;

int main()
{
	string S0, S1;
	cin >> S0 >> S1;

	if(S0.erase(0, S0.find('.') - 1) > S1.erase(0, S1.find('.') - 1))
	{
		cout << "YES" << endl;
		return 0;
	}
	if(S0.erase(S0.find('.') + 1, S0.rfind('.') - 1 - S0.find('.') + 1)
	   > S1.erase(S1.find('.') + 1, S1.rfind('.') - 1 - S1.find('.') + 1))
	{
		cout << "YES" << endl;
		return 0;
	}
	if(S0.erase(S0.rfind('.') + 1, S0.length() - S0.rfind('.') + 1)
		> S1.erase(S1.rfind('.') + 1, S1.length() - S1.rfind('.') + 1))
	{
		cout << "YES" << endl;
		return 0;
	}

	cout << "NO" << endl;
	return 0;
}