import java.util.Scanner;

public class Main {
	public static Scanner scan = new Scanner(System.in);
	public static int n;
	public static void main(String args[]){
		run();
	}
	static void run(){
		int n, firstPriceTmp, priceTmp;
		int minPrice, maxPrice;
		int maxBenefit, benefit;
		
		maxBenefit = -(1000000000 - 1);
		minPrice = 1000000000;
		maxPrice = 1;
		n = scan.nextInt();
		
		firstPriceTmp = scan.nextInt();
		for(int i = 1; i < n; i++){
			priceTmp = scan.nextInt();
			minPrice = Math.min(minPrice, firstPriceTmp);
			firstPriceTmp = priceTmp;
			benefit = priceTmp - minPrice;
			maxBenefit = Math.max(benefit, maxBenefit);
		}
		System.out.println(maxBenefit);
	}
}
/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