using System;
using System.Collections.Generic;

namespace TriangleRight
{
	class MainClass
	{
		public static void Main(string[] args) 
		{
			string str; 
			List<string> status = new List<string> ();
			while (!string.IsNullOrEmpty(str = Console.ReadLine())) {
				string[] input = str.Split(' ');
				int a, b, c;
				if (input.Length > 2 && input.Length <= 3) {
					a = input [0].Equals ("") ? 0 : int.Parse (input [0]);
					b = input [1].Equals ("") ? 0 : int.Parse (input [1]);
					c = input [2].Equals ("") ? 0 : int.Parse (input [2]);
				} else {
					a = input [0].Equals ("") ? 0 : int.Parse (input [0]);
					b = 0;
					c = 0;
				}

				if (a + b > c) {
					if (a + c > b) {
						if (b + c > a) {
							status.Add ("YES");
						} else {
							status.Add ("NO");
						}
					} else {
						status.Add ("NO");
					}
				} else {
					status.Add ("NO");
				}
			};

			for (int i = 0; i < status.Count; i++) {
				Console.WriteLine (status[i]);
			}


			Console.Read ();
		}
	}
}