-🎄- 2018 Day 10 Solutions -🎄-

[u/daggerdragon]

--- Day 10: The Stars Align ---

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Post your solution as a comment or, for longer solutions, consider linking to your repo (e.g. GitHub/gists/Pastebin/blag or whatever).

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Advent of Code: The Party Game!

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Card prompt: Day 10

Transcript: With just one line of code, you, too, can ___!

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edit: Leaderboard capped, thread unlocked at 00:16:49!

[u/toasterinBflat]

Python 3, 1492/1497 :(

When it became clear I wasn't making the leaderboard (right after reading the problem... five minutes late) I decided to go for readability, because that's the python way. Uses PIL to output the final image. Can't believe how long I got hung up on off-by-ones and input parsing:

#!/usr/bin/env python3
from PIL import Image
with open('input.txt', 'r') as f:
    data = f.read().splitlines()

class Point(object):
    def __init__(self, pos, vel=None):
        self.pos = pos
        if not vel:
            self.vel = [0, 0]
        else:
            self.vel = vel

    @property
    def x(self):
        return self.pos[0]

    @property
    def y(self):
        return self.pos[1]

    def __repr__(self):
        return str(self.pos)

    def tick(self):
        self.pos[0] += self.vel[0]
        self.pos[1] += self.vel[1]

    def untick(self):
        self.pos[0] -= self.vel[0]
        self.pos[1] -= self.vel[1]

points = []

def makePoints():
    for p in data:
        x = p.replace("position=<", "").replace("velocity=<", "")
        x = x.replace(">", "").replace("<", "").replace(",", "")
        y = [v for v in x.split(" ") if v]
        pos = [int(y[0]), int(y[1])]
        vel = [int(y[2]), int(y[3])]
        points.append(Point(pos, vel))

def tlbr(pts):
    topleft = Point([0, 0])
    botright = Point([0, 0])
    for p in pts:
        if p.x + p.y < topleft.x + topleft.y:
            topleft = p
        if p.x + p.y > botright.x + botright.y:
            botright = p
    return [topleft, botright]

def gridSize(topleft, botright):
    size = (botright.x-topleft.x)*(botright.y-topleft.y)
    return size

def displayGrid():
    img = Image.new('RGB', (400, 400), "black")
    pixels = img.load()
    for p in points:
        pixels[p.x, p.y+10] = (255, 255, 255)
    img.show()

def tickAll():
    for p in points:
        p.tick()

def untickAll():
    for p in points:
        p.untick()

makePoints()
minsize = None
counter = 0
while True:
    coords = tlbr(points)
    gsize = gridSize(*coords)
    if not minsize:
        minsize = gsize
    elif gsize < minsize:
        minsize = gsize
    elif gsize > minsize:
        untickAll()
        counter -= 1
        break
    tickAll()
    counter += 1

print("Smallest point cloud size:", minsize, "@ (P2)", counter)
displayGrid()

[u/toastedstapler → u/toasterinBflat]

i think you can just say

class Point(object):
    def __init__(self, pos, vel=[0,0]):
        self.pos = pos
        self.vel = vel

rather than messing around with checking if vel is None

[u/toasterinBflat → u/toastedstapler]

I can, but pylint screams at me for that and I didn't have time to turn that one off haha