import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] r = new int[n];
    for(int i = 0; i < n; i++) {
      r[i] = sc.nextInt();
    }
    int max = r[1] - r[0];
    int min = r[0];
    for(int i = 1; i < n; i++) {
      min = Math.min(min, r[i - 1]);
      max = Math.max(max, 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