import java.util.Scanner;

public class Main{
    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        int n = Integer.valueOf(scan.next());
        int[] ns = new int[n];
        for(int i=0;i<n;i++) {
        	ns[i] = Integer.valueOf(scan.next());
        }
        int min = ns[0];
        int max = ns[1]-ns[0];
        for(int i=1;i<n;i++) {
        	if(max < ns[i]-min) {
        		max = ns[i]-min;
        	}
        	if(ns[i] < min) {
        		min = ns[i];
        	}
        }
        System.out.println(max);
        scan.close();
    }
}

/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