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

namespace pj12
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] speed = Console.ReadLine().Trim().Split(' ').Select(x => int.Parse(x)).ToArray();
            speed[0] = speed[0] * 1000 / 60 / 60;
            speed[1] = speed[1] * 1000 / 60 / 60;

            int coner = int.Parse(Console.ReadLine());

            String look = "YES";



            int[] road = new int[coner];
            int[] line = Console.ReadLine().Trim().Split(' ').Select(x => int.Parse(x)).ToArray();
            
            for(int i = 0;i < coner;i++)
            {
                road[i] = line[i];
            }

            int nowX = 0, nowY = 0;

            for(int i = 0;i < coner;i++)
            {
                for (int j = 0; j < coner;j++ )
                {
                    if(speed[0] <= 0)
                    {
                        nowX = j;
                    }
                    else
                    {
                        speed[0] -= road[j];
                    }

                    if (speed[1] <= 0)
                    {
                        nowY = j;
                    }
                    else
                    {
                        speed[1] -= road[j];
                    }

                    if(nowX - nowY > 1)
                    {
                        look = "NO";
                        break;
                    }
                }
                speed[0] += speed[0];
                speed[1] += speed[1];

            }
            Console.WriteLine(look);
        }
    }
}