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

public class Main {

	public static void main(String[] args) {
	      BufferedReader stdReader =new BufferedReader(new InputStreamReader(System.in));
	      try {
	    	  int N = Integer.parseInt(stdReader.readLine());
	    	  int K = Integer.parseInt(stdReader.readLine());
	    	  int max = 0;
	    	  int min = 1000;
	    	  int c = 0;
	    	  for(int i=0;i<N;i++){
	    		  c = Integer.parseInt(stdReader.readLine());
	    		  if(min>c) min = c;
	    		  if(max < c) max = c;
	    	  }
	    	  System.out.println(max-min);
	    	  } catch (IOException e) {
			e.printStackTrace();
	      }
	}
}