ChiPy Algorithms SIGDescription
Given a board with m by n cells, each cell has an initial state live (1) or dead (0). Each cell interacts with its eight neighbors (horizontal, vertical, diagonal) using the following four rules. Determine the next state.
- Live cell with fewer than two live neighbors dies, as if caused by under-population.
- Live cell with two or three live neighbors lives on to the next generation.
- Live cell with more than three live neighbors dies, as if by over-population..
- Dead cell with exactly three live neighbors becomes a live cell, as if by reproduction.
Solution
class Board:
def __init__(self, board):
import copy
self.board = copy.deepcopy(board)
self.rows = len(board)
self.cols = len(board[0])
self.board = []
for y in range(self.rows):
self.board.append([board[y][x] for x in range(self.cols)])
def value(self, y, x):
if x < 0 or y < 0:
return 0
if y >= self.rows:
return 0
if x >= self.cols:
return 0
if not self.board[y][x]:
return 0
return 1
def num_live_neighbors(self, y, x):
neighbors = []
for offset_y, offset_x in [(0,1),(1,0),(-1,1),(1,1)]:
neighbors.append(self.value(y+offset_y, x+offset_x))
neighbors.append(self.value(y-offset_y, x-offset_x))
return sum(neighbors)
def print(self):
for y in range(self.rows):
for x in range(self.cols):
if self.value(y,x):
print('*', end='')
else:
print('-', end='')
print()
def gameOfLife(board):
"""
Do not return anything, modify board in-place instead.
"""
board_obj = Board(board)
board_obj.print()
for y in range(board_obj.rows):
for x in range(board_obj.cols):
num_live_neighbors = board_obj.num_live_neighbors(y,x)
if board_obj.value(y,x): # Alive
if num_live_neighbors == 2 or num_live_neighbors == 3:
new_value = 1
else:
new_value = 0
else: # Dead
if num_live_neighbors == 3:
new_value = 1
else:
new_value = 0
board[y][x] = new_value
Board(board).print()
from pprint import pprint
board = [
[0,0,0,0,0,0,1,0],
[0,0,0,0,1,0,1,1],
[0,0,0,0,1,0,1,0],
[0,0,0,0,1,0,0,0],
[0,0,1,0,0,0,0,0],
[1,0,1,0,0,0,0,0],
]
while True:
gameOfLife(board)
input()