import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {

	public static void main(String[] args) throws Exception {
		BufferedReader r = new BufferedReader(new InputStreamReader(System.in));
		int n = readInt(r);
		int[] price = new int[n];
		for(int i = 0 ; i < n ; i++) price[i] = readInt(r);

		int max = -2000000000;
		int min = price[0];
		for(int x = 1 ; x < n ; x++){
			max = Math.max(max,price[x] - min);
			min = Math.min(min,price[x]);
		}

		System.out.println(max);
	}

	public static int readInt(BufferedReader r) throws Exception{
		return Integer.parseInt(r.readLine());
	}

}
/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