import java.util.Scanner;

class Main {
    
    public static void main(String[] args) {
        
        No0021 no = new No0021();

        System.out.println(no.result());
        
    }
    
}

class No0021 {
    private int n;
    private int k;
    private String result;
    
    public No0021() {
        Scanner sc = new Scanner(System.in);
        this.n = sc.nextInt();
        this.k = sc.nextInt();
        int min = sc.nextInt();
        int max = min;
        for (int i = 1; i < this.n; i++) {
            int val = sc.nextInt();
            if (val < min) {
                min = val;
            } else if (max < val) {
                max = val;
            }
        }
        int sub = max - min;
        this.result = String.valueOf(sub);
    }
    
    public String result() {
        return this.result;
    }
}