Day and Night on a Klein Bottle.py

# -*- coding: utf-8 -*-

import random

born = [3,6,7,8]
die = [0,1,2,5]

size = 30

def neighbors((x,y),g):
    for newx in [x-1,x,x+1]:
        for newy in [y-1,y,y+1]:
            if (newx == x) and (newy == y):
                continue
            else:
                if newx % size == newx: yield g[newx % size][newy % size]
                else: yield not g[newx % size][(size - newy) % size]

def randomGrid():
    grid = []
    for x in xrange(size):
        row = []
        grid.append(row)
        for y in xrange(size):
            row.append(random.choice([False,True]))
    return grid

def showGrid(g):
    rep = ''
    for row in g:
        for cell in row:
            if cell:
                rep += '■ '
            else:
                rep += '□ '
        rep += '\n'
    return rep

def step(g):
    newg = []
    for x in xrange(size):
        row = []
        newg.append(row)
        for y in xrange(size):
            if g[x][y]:
                if len([alive for alive in neighbors((x,y),g) if alive]) in die: row.append(False)
                else: row.append(True)
            else:
                if len([alive for alive in neighbors((x,y),g) if alive]) in born: row.append(True)
                else: row.append(False)
    return newg

g = randomGrid()
while True:
    print showGrid(g)
    ans = raw_input()
    if ans == 'q': break
    g = step(g)