C#-Code

using System;
using System.Text;
using System.Collections.Generic;
using System.Timers;
using System.IO;
using System.Reflection;

namespace trainYourProgrammer
{
	class MainClass
	{
		class Game
		{
			private struct Point {
				public int x, y; 
				public Point(int x, int y) {this.x = x; this.y = y; }
			}

			private enum FieldType {Free, Food, Poison, Antidote}
			private Timer timer;
			private enum Direction {Up, Right, Down, Left}
			private List<Point> snake;
			private Direction direction;
			private const int healthMax = 20;
			private int health;
			private Random random = new Random ();
			private FieldType[,] grid;
			private int width;
			private int height;
			private bool poisoned = false;
			private string highscorePath;

			public Game()
			{
				init();
			}

			private void init()
			{
				timer = new Timer(200);
				highscorePath = Path.GetDirectoryName(Assembly.GetExecutingAssembly ().Location) 
					+ Path.DirectorySeparatorChar + "score.txt";
				width = Console.WindowWidth;
				height = Console.WindowHeight;
				grid = new FieldType[width, height];
				snake = new List<Point> ();
				snake.Add(new Point(width / 2, height - 1));
				health = healthMax;
				placeFood();
				direction = Direction.Up;
				timer.Elapsed += gameTick;
				timer.Start();
				Console.CursorVisible = false;
			}

			private void placeFood()
			{
				List<Point> candidates = new List<Point> ();
				for (int i = 0; i < width; i++)
					for (int j = 0; j < height; j++) {
						Point p = new Point (i, j);
						if (snake.Contains (p) || Math.Abs(p.x - snake[0].x) + Math.Abs(p.y + snake[0].y) < 3)
							continue;
						if (grid [i, j] == FieldType.Free)
							candidates.Add (p);
					}
				int index = random.Next (candidates.Count);
				grid [candidates [index].x, candidates [index].y] = FieldType.Food;
				candidates.RemoveAt (index);
				if (random.NextDouble () < 0.02) {
					index = random.Next (candidates.Count);
					grid [candidates [index].x, candidates [index].y] = FieldType.Poison;
					candidates.RemoveAt (index);
				}
				if (random.NextDouble () < 0.01) {
					index = random.Next (candidates.Count);
					grid [candidates [index].x, candidates [index].y] = FieldType.Antidote;
					candidates.RemoveAt (index);
				}
			}

			private void gameTick(object sender, ElapsedEventArgs e)
			{
				Point headNew = snake [0];
				switch (direction) {
					case Direction.Up: headNew.y--; break;
					case Direction.Down: headNew.y++; break;
					case Direction.Right: headNew.x++; break;
					case Direction.Left: headNew.x--; break;
				}
				if (headNew.x < 0 || headNew.x >= width || headNew.y < 0 || headNew.y >= height) {
					die (); //ins Tigergehege entlaufen
					return;
				}
				snake.Insert (0, headNew);
				switch (grid [headNew.x, headNew.y]) {
					case FieldType.Poison: poisoned = true; break;
					case FieldType.Antidote: poisoned = false; health = healthMax; break;
				case FieldType.Food: snake.Add (snake [snake.Count - 1]); placeFood (); break;
				}
				snake.RemoveAt (snake.Count - 1);
				grid [headNew.x, headNew.y] = FieldType.Free;
				if (poisoned)
					health--;
				if (health <= 0) {
					die (); //vergiftet
					return;
				}
				for (int i = 1; i < snake.Count; i++)
					if (snake [i].x == snake [0].x && snake [i].y == snake [0].y) {
						die (); //in den Schwanz gebissen
						return;
					}
				printGame ();
			}

			private void printGame()
			{
				StringBuilder sb = new StringBuilder ();
				for (int y = 0; y < height; y++) {
					for (int x = 0; x < width; x++) {
						Point p = new Point (x, y);
						if (snake.Contains (p))
							sb.Append ('\u2587');
						else if (grid [x, y] == FieldType.Antidote)
							sb.Append ('\u2665');
						else if (grid [x, y] == FieldType.Food)
							sb.Append ('\u2615');
						else if (grid [x, y] == FieldType.Poison)
							sb.Append ('\u2620');
						else
							sb.Append ('');
					}
					if (y < height + 1)
						sb.AppendLine ();
				}
				Console.Clear ();
				Console.Write (sb.ToString ());
			}

			private void die()
			{
				//highscore
				timer.Dispose ();
				Console.Clear ();
				Console.WriteLine ("\n\n    Du hast verloren!\n\n    Highscores:\n\n");
				if (!File.Exists (highscorePath)) {
					StreamWriter swTmp = new StreamWriter (highscorePath);
					swTmp.Write ("");
					swTmp.Close ();
				}
				StreamReader sr = new StreamReader (highscorePath); //Mono scheint hier mit using nicht klarzukommen
				string[] lines = sr.ReadToEnd().Split('\n');
				sr.Close();
				List<int> scores = new List<int> ();
				List<string> names = new List<string> ();
				foreach (string s in lines) {
					if (s.Contains("\t")) {
						scores.Add (int.Parse (s.Substring (0, s.IndexOf ('\t'))));
						names.Add (s.Substring (s.IndexOf ('\t') + 1));
					}
				}
				int insertPos = 0;
				while (insertPos < scores.Count && snake.Count <= scores[insertPos])
					insertPos++;
				scores.Insert (insertPos, snake.Count);
				names.Insert (insertPos, "");
				for (int i = 0; i < scores.Count && i < 10; i++) 
					Console.WriteLine ("    {0:00}: {1,-20} {2:00}",  i + 1, names [i], scores [i]);
				Console.WriteLine ("\n    Deine Punkte: {0}", snake.Count);
				if (insertPos < 10) { //zu highscores hinzufügen
					Console.CursorVisible = true;
					Console.SetCursorPosition (8, 7 + insertPos);
					while (Console.KeyAvailable)
						Console.ReadKey (true);
					Console.Out.Flush ();
					names [insertPos] = Console.ReadLine ();
					StreamWriter sw = new StreamWriter (highscorePath);
					for (int i = 0; i < scores.Count && i < 10; i++) 
						sw.WriteLine (scores [i] + "\t" + names [i]);
					sw.Close ();
				} else
					Console.ReadKey ();
				//neustart
				init ();
			}

			public void turnRight()
			{
				direction = (Direction)(((int)direction + 1) % 4);
			}

			public void turnLeft()
			{
				direction = (Direction)(((int)direction + 3) % 4);
			}

			public bool IsRunning()
			{
				return timer.Enabled;
			}
		}

		static void Main(string[] args)
		{
			Game game = new Game ();
			while (true) {
				if (game.IsRunning () && Console.KeyAvailable) {
					ConsoleKey readKey = Console.ReadKey ().Key;
					if (readKey == ConsoleKey.RightArrow)
						game.turnRight ();
					if (readKey == ConsoleKey.LeftArrow)
						game.turnLeft ();
				}
			}
		}
	}
}