import java.util.*;

public class AverageDifference {
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);
        int N = scanner.nextInt();
        int K = scanner.nextInt();
        int[] num = new int[N];
        for(int i = 0 ; i < N ; i++){
            num[i] = scanner.nextInt();
        }
        
        Arrays.sort(num);
        
        System.out.print(num[N-1] - num[0]);
 
    }
    
}