4.4 Brave new world

using System;

namespace Lesson4_4
{
    class Program
    {
        static void Main(string[] args)
        {
            int numberCoins = 10;
            int collectedCoins = 0;

            var map = GenerationMap(20 , 30 , numberCoins);

            int heroX = 2;
            int heroY = 2;

            Console.CursorVisible = false;

            RenderMap(map);

            do
            {
                Console.SetCursorPosition(heroY , heroX);
                Console.Write('@');

                MoveHero(map , ref heroX , ref heroY);

                if (map[heroX , heroY] == '$')
                {
                    collectedCoins++;
                    map[heroX , heroY] = ' ';
                }
            }
            while (numberCoins != collectedCoins);
        }

        private static char[,] GenerationMap(int height , int width , int numberCoins)
        {
            var map = new char[height , width];

            var random = new Random();

            for (int i = 0; i < map.GetLength(0); i++)
            {
                for (int j = 0; j < map.GetLength(1); j++)
                {
                    if (i == 0 || j == 0 || i == map.GetLength(0) - 1 || j == map.GetLength(1) - 1)
                        map[i , j] = '#';
                    else
                        map[i , j] = ' ';
                }
            }

            int coinX;
            int coinY;

            bool restartSearch;

            for (int i = 0; i < numberCoins; i++)
            {
                do
                {
                    restartSearch = false;

                    coinX = random.Next(1 , map.GetLength(0) - 1);
                    coinY = random.Next(1 , map.GetLength(1) - 1);

                    if (map[coinX , coinY] == ' ')
                        map[coinX , coinY] = '$';
                    else
                        restartSearch = true;
                }
                while (restartSearch);
            }

            return map;
        }

        private static void RenderMap(char[,] map)
        {
            Console.SetCursorPosition(0 , 0);

            for (int i = 0; i < map.GetLength(0); i++)
            {
                for (int j = 0; j < map.GetLength(1); j++)
                {
                    Console.Write(map[i , j]);
                }
                Console.WriteLine();
            }
        }

        private static void MoveHero(char[,] map ,ref int heroX , ref int heroY)
        {
            ConsoleKeyInfo userInput = Console.ReadKey();

            switch (userInput.Key)
            {
                case ConsoleKey.UpArrow:
                    if (heroX != 0 && map[heroX - 1 , heroY] != '#')
                    {
                        heroX--;
                        RenderMap(map);
                    }
                    break;

                case ConsoleKey.DownArrow:
                    if (heroX != map.GetLength(0) - 1 && map[heroX + 1 , heroY] != '#')
                    {
                        heroX++;
                        RenderMap(map);
                    }
                    break;

                case ConsoleKey.LeftArrow:
                    if (heroY != 0 && map[heroX , heroY - 1] != '#' && heroY != 0)
                    {
                        heroY--;
                        RenderMap(map);
                    }
                    break;

                case ConsoleKey.RightArrow:
                    if (heroY != map.GetLength(1) - 1 && map[heroX , heroY + 1] != '#')
                    {
                        heroY++;
                        RenderMap(map);
                    }
                    break;
            }
        }
    }
}