Main

package org.example;
import java.util.ArrayList;

public class Main {

    public static void main(String[] args) {

        ArrayList<Person> personArrayList = new ArrayList<Person>();

        Person firstPerson = new Person("Mariia", 19);
        Person secondPerson = new Person("Nikolas",24);
        Person thirdPerson = new Person("Vin",20);

        Student firstStudent = new Student("Oleh", 20, 3);
        Student secondStudent = new Student("Olena", 10, 4);
        Student thirdStudent = new Student("Toni", 34, 2);

        personArrayList.add(firstPerson);
        personArrayList.add(secondPerson);
        personArrayList.add(thirdPerson);

        personArrayList.add(firstStudent);
        personArrayList.add(secondStudent);
        personArrayList.add(thirdStudent);

        for (int i = 0; i < personArrayList.size(); i++){
            System.out.println(personArrayList.get(i));
        }

        System.out.println("Comparing:");

        if(persons.get(0).compareTo(persons.get(1)) == 0){
            System.out.println("Ages are the same");
        } else if (persons.get(0).compareTo(persons.get(1)) > 0){
            System.out.println("1st age > 2nd age");
        } else {
            System.out.println("2nd age > 1st age");
    }
  }
}