using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

​

namespace ConsoleAppSnake

{

    public class Program

    {

        struct P : IEquatable<P>

        {

            public int x, y;

​

            public P(int x, int y)

            {

                this.x = x;

                this.y = y;

            }

​

            public bool Equals(P other)

            {

                return this.x == other.x && this.y == other.y;

            }

​

            public static P operator+(P a, P b)

            {

                return new P(a.x + b.x, a.y + b.y);

            }

​

            public static P operator -(P a, P b)

            {

                return new P(a.x - b.x, a.y - b.y);

            }

        }

​

        enum Dir

        {

            S,

            D,

            W,

            A                

        }

​

        static readonly P[] dirs = new[] { new P(0,1), new P(1,0), new P(0,-1), new P(-1,0) };

​

        const int fieldSize = 10;

        const int snakeStartLength = 5;

        const Dir snakeStartDir = Dir.D;

        static readonly P snakeStartPosition = new P(2, fieldSize / 2);

​

        //Только для рендера

        static int[,] field = new int[fieldSize, fieldSize];

​

        static LinkedList<P> snake;

        static Dir snakeDir;

​

        static void Init()

        {

            snake = new LinkedList<P>();

            snakeDir = snakeStartDir;

            P p = snakeStartPosition;            

            for (int i = 0; i < snakeStartLength; i++)

            {

                snake.AddFirst(p);

                p = p + dirs[(int)snakeStartDir];

            }            

        }

​

        static bool IsInsideField(P p)

        {

            return p.x >= 0 && p.x < fieldSize && p.y >= 0 && p.y < fieldSize;

        }

​

        static bool MoveSnake()

        {

            P head = snake.First();

            P newHead = head + dirs[(int)snakeDir];

​

            if (!IsInsideField(newHead))

                return false;

​

            //------->>> Проверка на самовъеб головой в тулово ЗДЕСЬ <<<---------

            foreach (P p in snake)

                if (newHead.Equals(p))

                    return false;

​

            snake.AddFirst(newHead);

            snake.RemoveLast();

            return true;

        }

​

        static void ClearRender()

        {

            for (int i = 0; i < fieldSize; i++)

                for (int j = 0; j < fieldSize; j++)

                    field[i, j] = 0;                

        }

​

        static void Render()

        {

            foreach (P p in snake)

                field[p.y, p.x] = 1;

            P head = snake.First();

            field[head.y, head.x] = 2;

        }

​

        static void Show()

        {           

            StringBuilder sb = new StringBuilder();

            for (int i = 0; i < fieldSize; i++)

            {

                for (int j = 0; j < fieldSize; j++)

                {

                    sb.Append(field[i, j].ToString());

                }

                Console.WriteLine(sb.ToString());

                sb.Clear();

            }

            Console.WriteLine("------------wsad, enter");

        }

​

​

        public static void Main(string[] args)

        {

            for (; ; )

            {

                Init();

​

                for (; ; )

                {

                    ClearRender();

                    Render();

                    Show();

                    string s = Console.ReadLine().ToUpper();

​

                    Dir d;

                    if (Enum.TryParse<Dir>(s, out d))

                    {

                        if(!(dirs[(int)d] + dirs[(int)snakeDir]).Equals(new P(0,0))) //Обратно ехай нельзя!

                            snakeDir = d;

                    }

​

                    if (!MoveSnake())

                    {

                        Console.WriteLine("Вы въебались!");

                        Console.WriteLine("------------------");

                        break;

                    }

                }

​

                Console.ReadLine();

            }

        }

    }

}

​