using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace yukicoderTest
{
    class Program
    {
        static void Main(string[] args)
        {
            string input = Console.ReadLine();
            string input2 = Console.ReadLine();
            string[] A0str = input.Split('.');
            string[] A1str = input2.Split('.');
            int[] A0 = new int[A0str.Length];
            int[] A1 = new int[A1str.Length];
            int cnt = 0;
            for (int i = 0; i < A0.Length; i++)
            {
                A0[i] = int.Parse(A0str[i]);
                A1[i] = int.Parse(A1str[i]);

                if(A0[i]>A1[i])
                {
                    Console.WriteLine("YES");
                    break;
                }
                else if(A0[i]<A1[i])
                {
                    Console.WriteLine("NO");
                    break;
                }
                else if(A0[i]==A1[i])
                {
                    cnt++;
                    if(cnt==A0.Length)
                    {
                        Console.WriteLine("YES");
                    }
                }
            }
            

        }

    }
}