import java.util.Scanner;

class Main{
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		int n=sc.nextInt(),r=sc.nextInt(),minv=r,maxv=Integer.MIN_VALUE;
		for(int i=1;i<n;++i) {
			r=sc.nextInt();
			maxv=Math.max(maxv, r-minv);
			minv=Math.min(minv, r);
		}
		sc.close();
		System.out.println(maxv);
	}
}

/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