//Game3.cs
using System;
using System.Collections.Generic;

namespace Pyatnyasky_v2
{
    class Game3 : Game2
    {
        Stack<Points> undo = new Stack<Points>();
        Stack<Points> redo = new Stack<Points>();
        public Game3(int[] point) : base(point)
        {
        }

        public void History(int value)
        {
            undo.Push(GetLocation(value));
        }
        public void Undo()
        {
            if (undo.Count > 0)
            {
                var point = undo.Pop();
                this.Move(point.x, point.y], this); //Вот здесь среда показывает синтаксическа ошибка
                redo.Push(point);
            }
            else throw new Exception("Unable to cancel");
        }

        public void Redo()
        {
            if (redo.Count > 0)
            {
                var point = redo.Pop();
                this.Move(point.x, point.y], this); //Вот здесь среда показывает синтаксическа ошибка
                undo.Push(point);
            }
        }

    }
}


//Game.cs
using System;
namespace Pyatnyasky
{
    class Points
    {

        public  int x, y;
        public Points(int x, int y)
        {
            this.x = x;
            this.y = y;
        }
    }
    class Game
    {

        public int[] point = new int[16];
        public int Length = 0;

        public static int[] ArrayText = new int[16];
        public const int width = 4, height = 4;
        public int[,] field = new int[width, height];
        public Points[] FieldValue = new Points[16];

        public Game(int[] point)
        {

            int r = 0;

            Length = width * height;

            for (int j = 0; j < height; j++)
            {
                for (int i = 0; i < width; i++)
                {
                    field[j, i] = point[r];
                    FieldValue[point[r]] = new Points(j, i);
                    r++;

                }
            }
        }

        public int this[int x, int y]
        {
            get
            {
                if (x < 0 || x >= width * height || y < 0 || y >= width * height)
                {
                    throw new ArgumentOutOfRangeException("the indexes do not fit");
                }
                return field[x, y];
            }
        }

        public Points GetLocation(int value)
        {

            return FieldValue[value];
        }
        public void drawField()
        {
            Console.WriteLine("____________________________________");
            for (int i = 0; i < width; i++)
            {
               for (int j = 0; j < height; j++)
                {
                    Console.Write(field[i, j] + "t");
                }
               Console.WriteLine();
            }
            Console.WriteLine("____________________________________");

        }
        public void Move(int value, Game3 obj)
        {
            try
            {
                if (value > 15 || value < 0)
                {
                    throw new ArgumentException();
                }
                int x = GetLocation(0).x;
                int y = GetLocation(0).y;

                int X = GetLocation(value).x;
                int Y = GetLocation(value).y;

                if ((X == x && (Y == y - 1 || Y == y + 1)) || (Y == y && (X == x - 1 || X == x + 1)))
                {
                    field[x, y] = value;
                    field[X, Y] = 0;

                    var vere = FieldValue[0];
                    FieldValue[0] = FieldValue[value];
                    FieldValue[value] = vere;

                    obj.History(value);
                }
                else
                {
                    throw new Exception();
                }
            }
            catch (ArgumentException)
            {
                Console.WriteLine("There is no such number: ");
            }
            catch (Exception)
            {
                Console.WriteLine("Along with this number is not 0: ");
            }

        }
    }
}