import java.util.Scanner;

class Main
{
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		
		int[] r = new int[200000];
		int kai = -1000000000;
		
		int n = scan.nextInt();
		
		for(int i=0; i<n; i++){
			r[i] = scan.nextInt();
		}
		int min = r[0];
		int max = -1000000000;
		
		for(int j=1; j<n; j++){
			if(max < r[j]-min){
				max = r[j] - min;
			}
			if(min > r[j]){
				min = r[j];
			}
		}
		
		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