Task: Conway's Game of Life
C#: using System;
using System.Text;
using System.Threading;
 
namespace ConwaysGameOfLife
{
    
    class Program
    {
        
        private const int DELAY = 50;
 
        
        private const ConsoleColor DEAD_COLOR = ConsoleColor.White;
        private const ConsoleColor LIVE_COLOR = ConsoleColor.Black;
 
        
        private const ConsoleColor EXTRA_COLOR = ConsoleColor.Gray;
 
        private const char EMPTY_BLOCK_CHAR = ' ';
        private const char FULL_BLOCK_CHAR = '\u2588';
 
        
        private static bool[,] board;
 
        
        private static int width = 32;
        private static int height = 32;
 
        
        private static bool loopEdges = true;
 
 
        static void Main(string[] args)
        {
            
            initializeDemoBoard();
 
            initializeConsole();
 
            
            while (!Console.KeyAvailable || Console.ReadKey(true).Key != ConsoleKey.Escape) {
                Program.drawBoard();
                Program.updateBoard();
 
                
                Thread.Sleep(DELAY);
            }
        }
 
        
        private static void initializeConsole()
        {
            Console.BackgroundColor = EXTRA_COLOR;
            Console.Clear();
 
            Console.CursorVisible = false;
 
            
            
            int width = Math.Max(Program.width, 8) * 2 + 1;
            int height = Math.Max(Program.height, 8) + 1;
            Console.SetWindowSize(width, height);
            Console.SetBufferSize(width, height);
 
            Console.BackgroundColor = DEAD_COLOR;
            Console.ForegroundColor = LIVE_COLOR;
        }
 
        
        private static void initializeRandomBoard()
        {
            var random = new Random();
 
            Program.board = new bool[Program.width, Program.height];
            for (var y = 0; y < Program.height; y++) {
                for (var x = 0; x < Program.width; x++) {
                    
                    Program.board[x, y] = random.Next(2) == 0;
                }
            }
        }
 
        
        private static void initializeDemoBoard()
        {
            Program.width = 3;
            Program.height = 3;
 
            Program.loopEdges = false;
 
            Program.board = new bool[3, 3];
            Program.board[1, 0] = true;
            Program.board[1, 1] = true;
            Program.board[1, 2] = true;
        }
 
        
        private static void drawBoard()
        {
            
            var builder = new StringBuilder();
 
            for (var y = 0; y < Program.height; y++) {
                for (var x = 0; x < Program.width; x++) {
                    char c = Program.board[x, y] ? FULL_BLOCK_CHAR : EMPTY_BLOCK_CHAR;
 
                    
                    builder.Append(c);
                    builder.Append(c);
                }
                builder.Append('\n');
            }
 
            
            Console.SetCursorPosition(0, 0);
            Console.Write (builder.ToString());
        }
 
        
        private static void updateBoard()
        {
            
            bool[,] newBoard = new bool[Program.width, Program.height];
 
            for (var y = 0; y < Program.height; y++) {
                for (var x = 0; x < Program.width; x++) {
                    var n = countLiveNeighbors(x, y);
                    var c = Program.board[x, y];
 
                    
                    
                    newBoard[x, y] = c && (n == 2 || n == 3) || !c && n == 3;
                }
            }
 
            
            Program.board = newBoard;
        }
 
        
        private static int countLiveNeighbors(int x, int y)
        {
            
            int value = 0;
 
            
            for (var j = -1; j <= 1; j++) {
                
                if (!Program.loopEdges && y + j < 0 || y + j >= Program.height) {
                    continue;
                }
 
                
                int k = (y + j + Program.height) % Program.height;
 
                for (var i = -1; i <= 1; i++) {
                    
                    if (!Program.loopEdges && x + i < 0 || x + i >= Program.width) {
                        continue;
                    }
 
                    
                    int h = (x + i + Program.width) % Program.width;
 
                    
                    value += Program.board[h, k] ? 1 : 0;
                }
            }
 
            
            return value - (Program.board[x, y] ? 1 : 0);
        }
    }
}

Java: public class GameOfLife{
	public static void main(String[] args){
		String[] dish= {
				"_#_",
				"_#_",
				"_#_",};
		int gens= 3;
		for(int i= 0;i < gens;i++){
			System.out.println("Generation " + i + ":");
			print(dish);
			dish= life(dish);
		}
	}

	public static String[] life(String[] dish){
		String[] newGen= new String[dish.length];
		for(int row= 0;row < dish.length;row++){
			newGen[row]= "";
			for(int i= 0;i < dish[row].length();i++){
				String above= "";
				String same= "";
				String below= "";
				if(i == 0){
					
					
					above= (row == 0) ? null : dish[row - 1].substring(i,
									i + 2);
					same= dish[row].substring(i + 1, i + 2);
					
					
					below= (row == dish.length - 1) ? null : dish[row + 1]
									.substring(i, i + 2);
				}else if(i == dish[row].length() - 1){
					
					
					above= (row == 0) ? null : dish[row - 1].substring(i - 1,
									i + 1);
					same= dish[row].substring(i - 1, i);
					
					
					below= (row == dish.length - 1) ? null : dish[row + 1]
									.substring(i - 1, i + 1);
				}else{
					
					
					above= (row == 0) ? null : dish[row - 1].substring(i - 1,
									i + 2);
					same= dish[row].substring(i - 1, i)
									+ dish[row].substring(i + 1, i + 2);
					
					
					below= (row == dish.length - 1) ? null : dish[row + 1]
									.substring(i - 1, i + 2);
				}
				int neighbors= getNeighbors(above, same, below);
				if(neighbors < 2 || neighbors > 3){
					newGen[row]+= "_";
				}else if(neighbors == 3){
					newGen[row]+= "#";
				}else{
					newGen[row]+= dish[row].charAt(i);
				}
			}
		}
		return newGen;
	}

	public static int getNeighbors(String above, String same, String below){
		int ans= 0;
		if(above != null){
			for(char x: above.toCharArray()){
				if(x == '#') ans++;
			}
		}
		for(char x: same.toCharArray()){
			if(x == '#') ans++;
		}
		if(below != null){
			for(char x: below.toCharArray()){
				if(x == '#') ans++;
			}
		}
		return ans;
	}

	public static void print(String[] dish){
		for(String s: dish){
			System.out.println(s);
		}
	}
}