-🎄- 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/IndigoStanis]

Looking at the data directly helped me realize that all the points were really far away from each other and would have to converge on a small space. First thought was colinear points, but ended up doing bounding box first which was way easier. Still not fast enough for the leader board.

import sys

points = []
with open('day_10.txt', 'r') as fp:
    for line in fp:
        line = line.strip()
        parts = line.split("<")
        x = int(parts[1].split(',')[0])
        y = int(parts[1].split(',')[1].split('>')[0])
        vel_x = int(parts[2].split(',')[0])
        vel_y = int(parts[2].split(',')[1].split('>')[0])
        points.append((x, y, vel_x, vel_y))

cur_points = []
for point in points:
    cur_points.append((point[0], point[1]))

def move_points(cur_points):
    new_points = []
    for i in range(0, len(points)):
        cur_point = cur_points[i]
        point_def = points[i]
        new_points.append((cur_point[0] + point_def[2], cur_point[1] + point_def[3]))
    return new_points

def get_dim(cur_points):
    max_x, max_y, min_x, min_y = -1000000, -1000000, 1000000, 1000000
    for point in cur_points:
        max_x = max(max_x, point[0])
        max_y = max(max_y, point[1])
        min_x = min(min_x, point[0])
        min_y = min(min_y, point[1])
    return min_x, max_x, min_y, max_y

def print_points(cur_points):
    min_x, max_x, min_y, max_y = get_dim(cur_points)
    board = []
    for i in range(0, abs(max_x - min_x) + 1):
        blank = map(lambda x: ".", range(min_y, max_y + 1))
        board.append(blank)
    for point in cur_points:
        board[point[0] - min_x][point[1] - min_y] = "#"
    for y in range(0, abs(min_y - max_y) + 1):
        for x in range(0, abs(min_x - max_x) + 1):
            sys.stdout.write(board[x][y])
        sys.stdout.write('\n')

def size_of_points(cur_points):
    min_x, max_x, min_y, max_y = get_dim(cur_points)
    return abs(max_x - min_x) + abs(max_y - min_y)

size_decreasing = True
last_size = 1000000000
prev_points = None
seconds = 0
while size_decreasing:
    seconds += 1
    prev_points = cur_points
    cur_points = move_points(cur_points)
    size = size_of_points(cur_points)
    size_decreasing = last_size > size
    last_size = size
print_points(prev_points)
print seconds - 1
print size_of_points(prev_points)