using System;
using System.Linq;
namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            var abc=Console.ReadLine().Split(' ').Select(s=>int.Parse(s)).ToList();
            abc.Sort();
            Console.WriteLine(abc[0]==abc[2]+abc[1]?"YES":"NO");
        }
    }
}

