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

namespace YukiCoder_Cs
{
    class Program
    {
        public static void Main()
        {
            var N = int.Parse(Console.ReadLine());
            var K = int.Parse(Console.ReadLine());
            var list = new int[N];
            for (int i = 0; i < N; ++i)
            {
                list[i] = int.Parse(Console.ReadLine());
            }
            Array.Sort(list);

            Console.WriteLine($"{list[N - 1] - list[0]}");
        }
    }
}