import java.util.Scanner;

public class Main
{
	public static void main(String args[])
	{
		Scanner input = new Scanner(System.in);
		int n = input.nextInt();
		int mnv = input.nextInt();
		int mxv, t;
		t = input.nextInt();
		mxv = t - mnv;
		if(t < mnv)
			mnv = t;	
		for(int i = 2; i < n; i++)
		{
			t = input.nextInt();
			if(t < mnv)
				mnv = t;
			else if(mxv < t - mnv)
				mxv	= t - mnv;
		}
		System.out.println(mxv);
	}
}
/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