from random import getrandbits
WIDTH = 80
HEIGHT = 23

def evolve (c):
    def new_cell(bit, n):
        if bit > 0:
            if n == 2 or n == 3:
                return 1
            else:
                return 0
        else:
            if n == 3:
                return 1
            else:
                return 0
    acc_y = []
    for y in xrange(HEIGHT):
        acc_x = []
        for x in xrange(WIDTH):
            if y == 0 and x == 0:
                neighbors = (c[y][x+1] + c[y-1][x] + c[y-1][x+1])
            elif y == HEIGHT-1 and x == WIDTH-1:
                neighbors = (c[y][x-1] + c[y-1][x-1] + c[y-1][x])
            elif y == 0 and x == WIDTH-1:
                neighbors = (c[y][x-1] + c[y+1][x-1] + c[y+1][x])
            elif y == HEIGHT-1 and x == 0:
                neighbors = (c[y-1][x] + c[y-1][x+1] + c[y][x+1])
            elif y == 0:
                neighbors = (c[y][x-1] + c[y][x+1] +
                             c[y+1][x-1] + c[y+1][x] + c[y+1][x+1])
            elif x == 0:
                neighbors = (c[y+1][x] + c[y+1][x+1] +
                             c[y][x+1] +
                             c[y-1][x] + c[y-1][x+1])
            elif y == HEIGHT-1:
                neighbors = (c[y][x-1] + c[y][x+1] +
                             c[y-1][x-1] + c[y-1][x] + c[y-1][x+1])
            elif x == WIDTH-1:
                neighbors = (c[y-1][x] + c[y-1][x-1] +
                             c[y][x-1] +
                             c[y+1][x] + c[y+1][x-1])
            else:
                neighbors = (c[y-1][x-1] + c[y-1][x] + c[y-1][x+1] +
                             c[y][x-1] + c[y][x+1] +
                             c[y+1][x-1] + c[y+1][x] + c[y+1][x+1])
            acc_x.append(new_cell(c[y][x],neighbors))
        acc_y.append(acc_x)
    return acc_y

def print_culture (c):
    for row in c:
        print "".join(['#' if bit > 0 else '_' for bit in row])

culture = [[int(getrandbits(1)) for x in xrange(WIDTH)]
           for y in xrange(HEIGHT)]

generation = 0

while True:
    print_culture(culture)
    usertext = raw_input("Generation " + str(generation) +
                         ": Input x to exit, or press Enter to continue. ")
    if usertext == "x":
        break
    else:
        generation +=1
        culture = evolve(culture)