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


public class Main {
    public static void main(String[] args) throws IOException {
        BufferedReader reader =new BufferedReader(new InputStreamReader(System.in));
        int N = Integer.parseInt(reader.readLine());
        int K = Integer.parseInt(reader.readLine());
        int max = Integer.MIN_VALUE;
        int min = Integer.MAX_VALUE;
        for (int i = 0; i < N; i++) {
            int n = Integer.parseInt(reader.readLine());
            max = Math.max(max,n);
            min = Math.min(min,n);
        }
        int difference = (max - min);
        System.out.println(difference);
    }
}