package b2015_5_31;

import java.util.Scanner;

public class KasekiVer {
public static void main(String[] args) {
	Scanner sc = new Scanner(System.in);
	String s1 = sc.nextLine();
	String s2 = sc.nextLine();
	String a = "";
	String b ="";
	int t1 = 0;
	int t2 = 0;
	int t3 = 0;
	int t4 = 0;
	int n1 = 1;
	int n2 = 1;
	int n3 = 0;
	t1 = Integer.parseInt(Nuki(s1, a, n1));
	t2 =  Integer.parseInt(Nuki(s2, b, n2));
	n1+=Nuki(s1, a, n1).length();
	n2+=Nuki(s2, b, n2).length();
	for(int i = 0; i < 4; i++){
		if(n3==3){
			System.out.println("YES");
			break;
		}else if(t1 > t2){
			System.out.println("YES");
			break;
		}else if(t1 < t2){
			System.out.println("NO");
			break;
		}else if(t1 == t2){
			a = "";
			b ="";
			t1 = 0;
			t2 = 0;
			t1 = Integer.parseInt(Nuki(s1, a, n1));
			t2 =  Integer.parseInt(Nuki(s2, b, n2));
			n1+=Nuki(s1, a, n1).length();
			n2+=Nuki(s2, b, n2).length();
			n3++;
		}
	}
}
public static String Nuki(String s, String ab, int n){
	while(!(s.substring(n-1, n)).equals(".")){
		ab+=s.substring(n-1, n);
		n++;
}
	return ab;
}
}