using System;
using System.IO;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Numerics;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using static System.Math;
using Int = System.Int64;
using Debug = System.Diagnostics.Debug;

class P
{
    static void Main()
    {
        int n = int.Parse(Console.ReadLine());
        int k = int.Parse(Console.ReadLine());
        var a = Enumerable.Repeat(0, n).Select(_ => int.Parse(Console.ReadLine())).ToList();
        Console.WriteLine(a.Max() - a.Min());
    }
}