import java.util.*;

public class Main {
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        int k=sc.nextInt();
        
        
        //これって最大の数字と最小の数字の差を出せばOk？
        int[] numbers=new int[n];
        for(int i=0;i<n;i++){
            numbers[i]=sc.nextInt();
        }
        Arrays.sort(numbers);
        System.out.println(numbers[numbers.length-1]-numbers[0]);
    }
}