import java.util.*;
class Main{
    int max(int a,int b){
	if(a<b)return b;
	else return a;
    }
    int min (int a,int b){
	if(a>b)return b;
	else return a;
    }
    Main(){
	Scanner sc =new Scanner(System.in);
	int a,c,d;
	a=sc.nextInt();
	d=-1000000000;
	c=sc.nextInt();
	for(int i=0;i<a-1;i++){
	    int f=sc.nextInt();
	    d=max(d,f-c);
	    c=min(c,f);
	}
	System.out.println(d);
    }
    public static void main (String[]arg){
	new Main();
    }
}
/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