using System.Collections.Generic;
using System;
using System.Drawing;
namespace yukicoder
{
    class Program
    {

        static void Main(string[] args)
        {
            var s = Console.ReadLine();
            var str = Console.ReadLine();
            
            List<char> list = new List<char>(s.Length);
            List<char> list2 = new List<char>(str.Length);
            int x = 0 , tencount = 0;

            

            for (int i = 0; i < s.Length; i++)
            {
                list.Add(s[i]);
            }

            for (int j = 0; j < str.Length; j++)
            {
                list2.Add(str[j]);
            }
           
           
            for(int m = 0; m < list.Count.CompareTo(list2.Count); m++)
            {
                if (list[m] == list2[m])
                {
                    list.Remove(list[m]);
                    list.Remove(list2[m]);
                }
                else if(!(list[m] == list2[m]))
                {
                    break;
                }
            }


            if (list[0].Equals("."))
            {
                Console.WriteLine("YES");
            }
            else if (list2[0].Equals("."))
            {
                Console.WriteLine("NO");
            }
            else if (!list[0].Equals(".") && !list2[0].Equals("."))
            {
                if (list[0] < list2[0])
                {
                    Console.WriteLine("NO");
                }
                else if (list[0] > list2[0])
                {
                    Console.WriteLine("YES");
                }
                else if (list.Count == list2.Count)
                {
                    Console.WriteLine("YES");
                }
            }
            
        }
    }
}