import java.util.*;
class Main{
	void aaaa(){
		Scanner sc=new Scanner(System.in);
		int N=sc.nextInt();
		int y;
		int min=2000000000;
		int x=-2000000000;
		for(int i=0;i<N;i++){
			y=sc.nextInt();
			if(y-min>x)x=y-min;
			if(min>y)min=y;
		}
		System.out.println(x);
	}
	public static void main(String[]arg){
		Main dn=new Main();
		dn.aaaa();
	}
}
/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