import java.util.*;
import java.math.*;
import java.io.*;
public class Main{
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String[] in1 = sc.next().split("\\.");
		String[] in2 = sc.next().split("\\.");
		int[] a1 = new int[3];
		int[] a2 = new int[3];
		for(int i = 0; i < 3; i++) {
			a1[i] = Integer.parseInt(in1[i]);
			a2[i] = Integer.parseInt(in2[i]);
		}
		for(int i = 0; i < 3; i++) {
			if(a1[i] > a2[i]) {
				System.out.println("YES");
				break;
			}
			if(a1[i] < a2[i]) {
				System.out.println("NO");
				break;
			}
			if(i == 2) {
				System.out.println("YES");
			}
		}
	}
 }