import java.util.*;
class Main{
  public static void main(String args[]){

    int max = -1000000000;
    int rt;
    int min;

    Scanner sc = new Scanner(System.in);
    // input
    int n = sc.nextInt();
    //first
    min = sc.nextInt();
    //Comparison
    for(int i = 1; i<n; i++){
      rt = sc.nextInt();
      if(rt-min>max)max = rt-min;
      if(min>rt)min = rt;

    }
    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