using System;

using System.Collections.Generic;

public class Program

{

    private static FilteredNumbers staticEvenFilteredNumbers = new FilteredNumbers(IsEven);

    public static void Main()

    {

        Console.WriteLine("Часть 1:");

        var evenNumbers = new FilteredNumbers(IsEven);

        evenNumbers.Add(1);

        evenNumbers.Add(2);

        evenNumbers.Add(3);

        // evenNumbers.IterateNumbers(NumberPrinter);

        Console.WriteLine("Часть 2:");

        var largeNumbers = new FilteredNumbers(IsGreaterThan5);

        largeNumbers.Add(3);

        largeNumbers.Add(4);

        largeNumbers.Add(5);

        largeNumbers.Add(6);

        //largeNumbers.IterateNumbers(MessagedNumberPrinter);

        Console.WriteLine("Часть 3:");

        evenNumbers.IterateNumbers(AddToEvenNumbers);

        largeNumbers.IterateNumbers(AddToEvenNumbers);

        //staticEvenFilteredNumbers.IterateNumbers(NumberPrinter);

    }

    private static bool IsEven(int num) => num % 2 == 0;

    private static bool IsGreaterThan5(int num) => num > 5;

    private static void NumberPrinter(int num) => Console.WriteLine(num);

    private static void MessagedNumberPrinter(int num) => Console.WriteLine($"Число равно {num}");

    private static void AddToEvenNumbers(int num) => staticEvenFilteredNumbers.Add(num);

}

​

public class FilteredNumbers

{

    private Filter filter;  

    private List<int> filteredNumbers = new();

    public FilteredNumbers(Filter filter)

    {

        this.filter = filter;

    }

    public void Add(int n) 

    {

        if (this.filter.Invoke(n))

        {

            this.filteredNumbers.Add(n);

        }

    }

    public void IterateNumbers(ActionOnNumber action)

    {

        foreach (var num in this.filteredNumbers)

        {

            action.Invoke(num);

        }

    }

}

​

public delegate bool Filter(int number);

public delegate void ActionOnNumber(int number);