import java.util.Scanner;

public class Main{
	public static void main(String[] args){
		Scanner sc=new Scanner(System.in);
		while(sc.hasNext()){
			String[] s0=(sc.next()).split("\\.");
			String[] s1=(sc.next()).split("\\.");
			for(int i=0;i<3;i++){
				if(s0[i].compareTo(s1[i])<0){
					System.out.println("NO");
					break;
				}
				else if(s0[i].compareTo(s1[i])>0){
					System.out.println("YES");
					break;
				}
			}
		}
	}
}