import java.util.*;
import java.io.*;
class Aaf {
  public static void main(String[] args){
    Scanner scan = new Scanner(System.in);
    int N = scan.nextInt();
    int K = scan.nextInt();
    int [] n = new int [N];
    for(int i=0; i<N; i++) n[i] = scan.nextInt();
    Arrays.sort(n);
    int c = n[N-1] - n[0];
    System.out.println(c);
  }
}