import java.lang.*;
import java.io.*;
import java.util.ArrayList;
import java.util.Collections;

class Yuki21 {
  public static void main(String[] args) throws IOException {
    DataInputStream d;
    d = new DataInputStream(System.in);
    String s;
    s = d.readLine();
    int n;
    n = Integer.parseInt(s);
    s = d.readLine();
    int k;
    k = Integer.parseInt(s);
    ArrayList<Integer> al;
    al = new ArrayList<Integer>();
    for(int i=0; i<n; ++i){
      s = d.readLine();
      int ni;
      ni = Integer.parseInt(s);
      al.add(ni);
    }
    Collections.sort(al);
    int a,b,c;
    a = al.get(n-1);
    b = al.get(0);
    c = a-b;
    System.out.println(c);
  }
}