import java.util.*;

public class Main{
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		ArrayList<Integer> R = new ArrayList<Integer>();
		int n, max = -1000000000, minR;
		
		n = sc.nextInt();
		for(int i = 0; i < n; i++){
			R.add(sc.nextInt());
		}
		
		minR = R.get(0);
		for(int i = 1; i < n; i++){
			max = Math.max(max, R.get(i)-minR);
			minR = Math.min(minR, R.get(i));
		}
		
		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