import java.util.*;

class Main {

    void solve() {
		Scanner in = new Scanner(System.in);
		int n = in.nextInt();
		int max = Integer.MIN_VALUE, min = Integer.MAX_VALUE;
		for(int i = 0; i < n; i++){
			int r = in.nextInt();
			max = Math.max(max, r - min);
			min = Math.min(min, r);
		}
		System.out.println(max);
	}

    public static void main(String[] args) {
        new Main().solve();
    }
}
/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