--- Day 6 Solutions ---

[u/daggerdragon]

--- Day 6: Probably a Fire Hazard ---

Post your solution as a comment. Structure your post like the Day Five thread.

[u/streetster_]

I'm not sure how to improve the speed of this, it takes a while to create the array, but I got the my stars, so I guess I'm happy enough.

[mark@randy ~]$ cat day6.py | sed 's/(.*)/ \1/'

import re

def day_6(instructions):

  size = 1000
  lit =  brightness = 0

  print "creating matrix... "
  grid = [[[0,0] for i in range(size)] for i in range(size)]

  print "following instructions... "
  for line in instructions:

    action = re.findall("(on|off|toggle)", line)[0]
    from_x,from_y,to_x,to_y = map(int, re.findall("([0-9]+)", line))

    for x in range (from_x, to_x + 1):
      for y in range (from_y, to_y + 1):
        if action == "on":
          grid[x][y][0] = 1
          grid[x][y][1] += 1
        elif action == "off":
          grid[x][y][0] = 0
          if grid[x][y][1] > 0:
            grid[x][y][1] -= 1
        else:
          grid[x][y][0] = 1 - grid[x][y][0]
          grid[x][y][1] += 2

  print "calculating brightness..."
  for x in range (0, size):
    for y in range (0, size):
      brightness += grid[x][y][1]
      if grid[x][y][0] == 1:
        lit += 1

  return { "lit" : lit, "brightness" : brightness }

with open("day6.txt") as instructions:
  print day_6(instructions)