import java.io.IOException;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws IOException {
		Scanner s = new Scanner(System.in);

		int n = s.nextInt();
		
		int max = -2000000000;
		int min = s.nextInt();
		
		for (int i = 1; i < n; i++) {
			int r = s.nextInt();
			max = Math.max(max, r-min);
			min = Math.min(min, r);
		}
		
		System.out.println(max);
	}
}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz