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using System;

class Person {
    public string name;
    public int age;
    
    // We can use other classes as datatypes for a field in a class
    public Address address;
    
    // We can use the class itself as a datatype for a field as well
    public Person father;
    public Person mother;
}

class Address {
    public string Country;
    public string City;
}

public class ConsoleApp
{
    public static void Main(string[] args)
    {
        Person p1 = new Person();
        p1.name = "Mihaly";
        p1.age = 21;
        
        Person p2 = new Person();
        p2.name = "Ann";
        p2.age = 52;
        
        Person p3 = new Person();
        p3.name = "Nagy";
        p3.age = 51;
        
        p1.mother = p2;
        p1.father = p3;
        
        Address address = new Address();
        address.Country = "Hungary";
        address.City = "Budapest";
        
        // Assigning the address object to the address field in p1
        p1.address = ___;
        
        // Note the expression 'p1.address.Country'
        // p1.address accesses the stored Address object
        // p1.address.Country accesses the Address object's Country field.
        Console.WriteLine($"{___} is the son of {p2.name} and {p3.name}. He is from {___}.");
    }
}