game_of_life.py

import random, time, copy

def new_grid(width, height):
    grid = []
    for x in range(width):
        column= []
        for y in range(height):
            column.append('#' if random.randint (0,1) else ' ')
        grid.append(column)
    return grid

def test_grid1():
    return [[' ', ' ', ' '],
            [' ', '#', ' '],
            [' ', ' ', ' ']
            ]

def test_grid2():
    return [[' ', ' ', ' ', ' ', ' ', ' '],
            [' ', ' ', ' ', '#', ' ', ' '],
            [' ', '#', ' ', '#', ' ', ' '],
            [' ', ' ', '#', '#', ' ', ' '],
            [' ', ' ', ' ', ' ', ' ', ' '],
            [' ', ' ', ' ', ' ', ' ', ' '],
            ]

def display(grid):
    """Print a grid on screen with asterisk border"""
    print("*" * (len(grid[0])+2))
    for row in grid:
        print("*", end='')
        print(''.join(row), end='')
        print("*")
    print("*" * (len(grid[0])+2))

def display_neighbors(grid):
    """Show the neighbor count of each position"""
    print("*" * (len(grid[0])+2))
    g = copy.deepcopy(grid)
    for y in range(len(grid)):
        for x in range(len(grid[0])):
            g[y][x] = str(count_neighbours(grid, x ,y))
    for row in g:
        print("*", end='')
        print(''.join(row), end='')
        print("*")
    print("*" * (len(grid[0])+2))

def display_changes(grid):
    """Show 'A' for dead cells becoming alive, 'd' for live cells dying, and '#'/' ' for unchanged"""
    g2 = step(grid)
    print("*" * (len(grid[0])+2))
    for y in range(len(grid)):
        print('*', end='')
        for x in range(len(grid[0])):
            if grid[y][x] == g2[y][x]: print(grid[y][x], end='')
            elif grid[y][x] == '#': print('d', end='')
            else: print('A', end='')
        print('*')
    print("*" * (len(grid[0])+2))

def count_neighbours(grid, x,y):
    neighbors = 0
    for i in range(-1,1+1):
        for j in range(-1,1+1):
            nx = (x + i) % len(grid)
            ny = (y + j) % len(grid[0])
            #print(f"i: {i} j: {j} nx: {nx} ny: {ny} cell value: {grid[ny][nx]}")
            if i == 0 and j == 0:
                continue
            if grid[ny][nx] == '#': 
                neighbors +=1
    #print(f"neighbors: {neighbors}")
    return neighbors

def game_of_life_rules(cell_value, neighbors):
    ##Any live cell with two or three live neighbours survives.
    ##Any dead cell with three live neighbours becomes a live cell.
    ##All other live cells die in the next generation. Similarly, all other dead cells stay dead.
    if cell_value == '#' and neighbors in (2, 3): return '#'
    elif cell_value == ' ' and neighbors == 3: return '#'
    else: return ' '

def step(grid):
    """Return the successor grid according to Conway's Game of Life"""
    g = copy.deepcopy(grid) # don't modify the list reference in place
    for y in range(len(grid)):
        for x in range(len(grid[0])):
            # read from input array, "grid"
            neighbors = count_neighbours(grid, x, y)
            # write to output array, "g"
            g[y][x] = game_of_life_rules(grid[y][x], neighbors)
    return g

if __name__ == '__main__':
    game_grid = test_grid2()
    for i in range(20):
        print(f"Generation {i}")
        display(game_grid)
        game_grid = step(game_grid)