import java.util.Scanner;

public class Main {
  public static void main(String[] args) {
    Scanner stdIn = new Scanner(System.in);
    int n = stdIn.nextInt();
    int max = -2000000000;
    int min = stdIn.nextInt();
    for (int i = 1; i < n; i++) {
      int now = stdIn.nextInt();
      if (now - min > max) 
        max = now - min;
      if (now < min)
        min = now;
    }
    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