import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner sc =new Scanner(System.in);
        int z = sc.nextInt();
        int[] r = new int[z];
        for(int i = 0; i < z; i++){
            r[i] = sc.nextInt();
        }
        int min = r[0];
        int max = r[1] - min;
        for(int i = 1; i < r.length; i++){
            max = max > r[i] - min ? max : r[i] - min;
            min = min > r[i] ? r[i] : min;
        }
        System.out.println(max);
    }
}
/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