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#!/usr/bin/env python
import numpy as np
from scipy.ndimage import convolve
with open('day18.txt') as data:
grid = np.stack([list(map(lambda x: x == '#', line.strip())) for line in data]).astype(int)
neighbors = [[1, 1, 1],
[1, 0, 1],
[1, 1, 1]]
grid1 = np.copy(grid)
for i in range(100):
neighbor_counts = convolve(grid1.astype(int), neighbors, mode='constant', cval=0)
survive = grid1 * (neighbor_counts >= 2) * (neighbor_counts <= 3)
grid1 = np.where(neighbor_counts == 3, True, survive)
print(np.count_nonzero(grid1))
grid2 = np.copy(grid)
for coord in {(0,0), (0, 99), (99, 0), (99, 99)}:
grid2[coord] = True
for i in range(100):
neighbor_counts = convolve(grid2.astype(int), neighbors, mode='constant', cval=0)
survive = grid2 * (neighbor_counts >= 2) * (neighbor_counts <= 3)
grid2 = np.where(neighbor_counts == 3, True, survive)
for coord in {(0,0), (0, 99), (99, 0), (99, 99)}:
grid2[coord] = True
print(np.count_nonzero(grid2))
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