import java.util.Scanner;

public class Main {
	public static void main(String args[]){
		int MAX = 200000;
		int[] R = new int[MAX];
		
		Scanner scan = new Scanner(System.in);
		int n = scan.nextInt();
		
		for(int i = 0; i < n; i++){
			R[i] = scan.nextInt();
		}
		
		int maxv = -2000000000; //???????°??????????????????????????¨????
		int minv = R[0];
		
		for(int i = 1; i < n; i++){ //????????§??????R[i]?????????????????°???????????????
			maxv = R[i] - minv > maxv ? R[i] - minv : maxv; //?????§????????´??°
			minv = R[i] < minv ? R[i] : minv; //???????????§???????°?????????????????????????
		}
		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