import java.time.LocalDate;
import java.util.Scanner;

/*
* Prog4 class
* - Revised structure to use Binary Search Tree of Persons
* - Revised structure to use Dynamic Linked List of Donations
* - Added option to save persons and donations to file
* - Added options to load persons and donations from file
*/
public class Prog4 {

// Method to display menu
public static int displayMenu(Scanner s) {
System.out.println("Current available commands:");
System.out.println("1 --> Print all donors");
System.out.println("2 --> Search for a donor");
System.out.println("3 --> Search for a blood type");
System.out.println("4 --> Add new donor");
System.out.println("5 --> Add new donation");
System.out.println("6 --> Find compatible blood donors");
System.out.println("7 --> Write database to files");
System.out.println("8 --> Load database from files");
System.out.println("9 --> Exit");
while (true) {
   System.out.print("Your choice? ");
   String input = s.nextLine();
   if (input.equals("1")) return 1;
   else if (input.equals("2")) return 2;
   else if (input.equals("3")) return 3;
   else if (input.equals("4")) return 4;
   else if (input.equals("5")) return 5;
   else if (input.equals("6")) return 6;
   else if (input.equals("7")) return 7;
   else if (input.equals("8")) return 8;
   else if (input.equals("9")) return 9;
   else System.out.println("Error: Invalid choice\n");
}
}

// Main method for program execution
public static void main(String[] args) {
if (args.length < 2) {
   System.out.println("Error: Please specify personfile donationfile");
   return;
}
//args = new String[2];
//args[0] = "personfile";
//args[1] = "donationfile";
Database database = new Database();
// Load persons file
if (args.length >= 1)
   database.loadPersons(args[0]);
// Load donations file
if (args.length >= 2)

Write a program ChatBot.java, where the user inputs a one-line sent...