using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var n = ReadLine().Split(' ');
        var set = new HashSet<string>(n);
        var list = new List<string>(set);
        var dic = new Dictionary<string, int>();
        for (var i = 0; i < list.Count; ++i) dic[list[i]] = i;
        var cmp = new int[n.Length];
        for (var i = 0; i < n.Length; ++i) cmp[i] = dic[n[i]];
        var bitmax = 1 << list.Count;
        for (var b = 0; b < bitmax; ++b)
        {
            var map = new bool[list.Count];
            var tmp = b;
            for (var i = 0; i < map.Length; ++i)
            {
                map[i] = tmp % 2 == 1;
                tmp >>= 1;
            }
            if (Nand(Nand(Nand(map[cmp[0]], map[cmp[1]]), map[cmp[2]]), Nand(Nand(map[cmp[3]], map[cmp[4]]), map[cmp[5]])))
            {
                WriteLine("YES");
                return;
            }
        }
        WriteLine("NO");
    }
    static bool Nand(bool a, bool b)
    {
        return !(a & b);
    }
}