Advent-of-Code/2021/11/main2.py
2021-12-13 13:59:07 -05:00

50 lines
1.4 KiB
Python

grid = []
to_flash = []
for line in open('data', 'r'):
grid_line = []
for ch in line.strip():
grid_line.append(int(ch))
grid.append(grid_line)
flashed = 0
step = 0
#for step in range(0, 100):
while(True):
# Step 1: Increment
for y in range(0, len(grid)):
for x in range(0, len(grid[y])):
grid[y][x] += 1
if(grid[y][x] > 9):
to_flash.append(tuple([y, x]))
# Step 2: Flash
prior_flash = flashed
while(len(to_flash)):
cell = to_flash[-1] # take the last one
to_flash.pop() # remove
flashed += 1 # count
for y in range(-1, 2):
new_y = cell[0] + y
if(new_y >= 0 and new_y < len(grid)): # in bounds
for x in range(-1, 2):
new_x = cell[1] + x
if(new_x >= 0 and new_x < len(grid[y])): # in bounds
grid[new_y][new_x] += 1
if(grid[new_y][new_x] == 10): # JUST flashed
to_flash.append(tuple([new_y, new_x]))
# PART TWO ANSWER
if(flashed - prior_flash == len(grid) * len(grid[0])):
print('all flash step #', step + 1)
break
# Step 3: Reset (if flashed)
for y in range(0, len(grid)):
for x in range(0, len(grid[y])):
if(grid[y][x] > 9):
grid[y][x] = 0
print('Step #', (step + 1), ': ', flashed)
step += 1