Advent of Code 2018 Day 3 solution and visualizer

common.py

import sys
import re
from os.path import join, dirname
from collections import namedtuple

class Claim(namedtuple("Claim", ['id', 'x', 'y', 'width', 'height'])):
    __slots__ = ()

    def find(self, array):
        return array[self.x:self.x+self.width, self.y:self.y+self.height]

def find_input(file_name):
    return join(dirname(sys.argv[0]), file_name)

def parse_claim(claim_string):
    return Claim(*([int(field) for field in re.match(r'#(\d+) @ (\d+),(\d+): (\d+)x(\d+)', claim_string).groups()]))

def parse_claims(claim_list):
    return [parse_claim(c) for c in claim_list]

problem1.py

import numpy

from common import parse_claims, find_input


def plot_claims(claims_list):
    fabric = numpy.zeros((1000, 1000), dtype=int)
    for claim in claims_list:
        claim_area = claim.find(fabric)
        claim_area += 1
    return fabric


if __name__ == "__main__":
    input_path = find_input("input.txt")
    with open(input_path) as input_file:
        puzzle_input = input_file.readlines()
        fabric = plot_claims(parse_claims(puzzle_input))
    print((1 < fabric).sum())

problem2.py

import numpy
from common import parse_claims, find_input
from problem1 import plot_claims


def find_free_claim(claims, fabric):
    for claim in claims:
        claim_area = claim.find(fabric)
        if (claim_area == 1).all():
            return claim
    return -1


if __name__ == "__main__":
    input_path = find_input("input.txt")
    with open(input_path) as input_file:
        puzzle_input = input_file.readlines()
        claims = parse_claims(puzzle_input)
        fabric = plot_claims(claims)
        result = find_free_claim(claims, fabric)

    print(result.id)

visualize.py

import pygame
import math
from pygame.locals import *
from pygame.transform import scale
from common import find_input, parse_claims
from problem1 import plot_claims
from problem2 import find_free_claim

try:
    import numpy
    import pygame.surfarray as surfarray
except ImportError:
    raise ImportError("NumPy and Surfarray are required.")

pygame.init()
screen_size = (2000, 2000)
img_size = (1000, 1000)
screen = pygame.display.set_mode(screen_size, 0, 32)
done = False
pygame.display.set_caption("Santa's suit plot")

input_path = find_input("input.txt")
with open(input_path) as input_file:
    puzzle_input = input_file.readlines()
    claims = parse_claims(puzzle_input)
    fabric = plot_claims(claims)
    free_claim = find_free_claim(claims, fabric)

img = numpy.zeros((*img_size, 3))
img[:] = (30, 30, 30)
img *= fabric[:, :, numpy.newaxis]
free_claim.find(img)[:] = (0, 255, 0)
temp_surface = pygame.Surface(img_size)
while not done:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True
    surfarray.blit_array(temp_surface, img)
    #HiDPI support
    scale(temp_surface, screen_size, screen)
    pygame.display.flip()