using System.Collections.Generic;
using System;
using System.Linq;
using System.Drawing;

namespace yukicoder
{
    class Program
    {

        static void Main(string[] args)
        {
            int N = int.Parse(Console.ReadLine());
            int K = int.Parse(Console.ReadLine());
            string[] strings = new string[N];
            float[] ints = new float[N];
            for (int i = 0; i < N; i++)
            {
                strings[i] = Console.ReadLine();
            }
            Array.Sort(strings);

            for(int j = 0; j < strings.Length; j++)
            {
                ints[j] = float.Parse(strings[j]);
            }

            var hiave = ints[N - 1] / 1;
            var lowave = ints[0] / 1;
            var ans = Math.Ceiling(hiave - lowave);
            Console.WriteLine(ans);
        }
    }
}