using System;

using System.Text.Json;

using System.Security.Cryptography;

public class Program

{

    public static void Main()

    {

        int[] x = new[] {5,6,7};

        int p = 0;

​

        Console.WriteLine(string.Join(",", x[0..(p + 2)]));

        Console.WriteLine(x[p]);

        Console.WriteLine($"p = {p}");

​

        Console.WriteLine(string.Join(",", x[0..(p += 2)]));

        Console.WriteLine(x[p]);

        Console.WriteLine($"p = {p}");

    }

}