import java.util.Scanner;

class Main{
  public static void main(String[] args){
    Scanner stdIn = new Scanner(System.in);
    int n = stdIn.nextInt();
    int[] r = new int[n];
    for(int i = 0; i < n; i++){
      r[i] = stdIn.nextInt();
    }

    int min = r[0];
    int maxp = r[1] - r[0];
    for(int i = 1; i < n; i++){
      int prof = r[i] - min;
      if(prof > maxp)
        maxp = prof;
      if(r[i] < min)
        min = r[i];
    }

    System.out.println(maxp);
  }
}
/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