using System;

using System.Collections.Generic;

public class Program

{   

    public static void Main()

    {

        Woman woman1 = new Woman("Hannah");

        Woman woman2 = new Woman("Wendy");

        Woman woman3 = new Woman("Alice");

        Man man1 = new Man("John");

        Man man2 = new Man("Fabian");

        Man man3 = new Man("Andrei");

        Man man4 = new Man("Krishna");

        Dictionary<IPerson, int> scores = new Dictionary<IPerson, int>();       

        scores.Add(woman1, 89);

        scores.Add(woman2, 90);

        scores.Add(woman3, 82);

        scores.Add(man1, 89);

        scores.Add(man2, 87);       

        scores.Add(man3, 84);

        scores.Add(man4, 85);

    }

}

​

public interface IPerson

{   

    string GetGender();

}

​

public class Man : IPerson

{

    public static int IDCounter = 0;

    public int Id { get; set; }

    public Man(string name)

    {

        this.Id = IDCounter++;

        this.Name = name;

    }

    public string Name { get; set; }

    public string GetGender()

    {

        return "Male";

    }

    public override bool Equals(object obj)

    {

        var man = obj as Man;

        if(man == null)

        {

            return false;

        }

        return this.Id == man.Id;

    }

    public override int GetHashCode()

    {

        return this.Id.GetHashCode();

    }

}

​

public class Woman : IPerson

{

    public static int IDCounter = 0;

    public int Id { get; set; }

    public Woman(string name)

    {

        this.Id = IDCounter++;

        this.Name = name;

    }   

    public string Name { get; set; }

    public string GetGender()

    {

        return "Female";

    }

    public override bool Equals(object obj)

    {

        var woman = obj as Woman;

        if(woman == null)

        {

            return false;

        }

        return this.Id == woman.Id;

    }

    public override int GetHashCode()

    {

        return this.Id.GetHashCode();

    }

}