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);
        }
    }
}

Go: package main

import (
	"bytes"
	"fmt"
	"math/rand"
	"time"
)

type Field struct {
	s    [][]bool
	w, h int
}

func NewField(w, h int) Field {
	s := make([][]bool, h)
	for i := range s {
		s[i] = make([]bool, w)
	}
	return Field{s: s, w: w, h: h}
}

func (f Field) Set(x, y int, b bool) {
	f.s[y][x] = b
}

func (f Field) Next(x, y int) bool {
	on := 0
	for i := -1; i <= 1; i++ {
		for j := -1; j <= 1; j++ {
			if f.State(x+i, y+j) && !(j == 0 && i == 0) {
				on++
			}
		}
	}
	return on == 3 || on == 2 && f.State(x, y)
}

func (f Field) State(x, y int) bool {
	for y < 0 {
		y += f.h
	}
	for x < 0 {
		x += f.w
	}
	return f.s[y%f.h][x%f.w]
}

type Life struct {
	w, h int
	a, b Field
}

func NewLife(w, h int) *Life {
	a := NewField(w, h)
	for i := 0; i < (w * h / 2); i++ {
		a.Set(rand.Intn(w), rand.Intn(h), true)
	}
	return &Life{
		a: a,
		b: NewField(w, h),
		w: w, h: h,
	}
}

func (l *Life) Step() {
	for y := 0; y < l.h; y++ {
		for x := 0; x < l.w; x++ {
			l.b.Set(x, y, l.a.Next(x, y))
		}
	}
	l.a, l.b = l.b, l.a
}

func (l *Life) String() string {
	var buf bytes.Buffer
	for y := 0; y < l.h; y++ {
		for x := 0; x < l.w; x++ {
			b := byte(' ')
			if l.a.State(x, y) {
				b = '*'
			}
			buf.WriteByte(b)
		}
		buf.WriteByte('\n')
	}
	return buf.String()
}

func main() {
	l := NewLife(80, 15)
	for i := 0; i < 300; i++ {
		l.Step()
		fmt.Print("\x0c")
		fmt.Println(l)
		time.Sleep(time.Second / 30)
	}
}