import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
	public static void main(String[] args) {
		BufferedReader buff = new BufferedReader(new InputStreamReader(System.in));

		try{
			int N = Integer.parseInt(buff.readLine());
			int K = Integer.parseInt(buff.readLine());
			int[] box = new int[N];
			for(int i = 0; i < N; ++i){
				box[i] = Integer.parseInt(buff.readLine());
				for(int j = 0; j < i; ++j){
					if(box[i] < box[j]){
						int w = box[i];
						box[i] = box[j];
						box[j] = w;
					}
				}
			}

			int posiMin = 0, posiMax = N -1;
			int max = box[posiMax], min = box[posiMin];

			int ans =  max - min;
			System.out.println(ans);


		} catch (NumberFormatException e) {

		} catch (IOException e) {

		}
	}
}