import java.util.Scanner;
class Main {
	static final int MAX = 200000;
	public static void main(String[] args) {
		int[] R = new int[MAX];
		int n;
		Scanner in = new Scanner(System.in);
		n = in.nextInt();
		for(int i = 0;i<n;i++) R[i] = in.nextInt();
		
		int maxv = R[1]-R[0];
		int minv = R[0];
		for(int i = 1;i<n;i++){
			if(maxv < R[i] - minv) maxv = R[i]-minv;	
			if(minv>R[i]) minv = R[i];
		}
		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