Advent of Code, day 12 - 2022

advent_12_2022.py

"""
SPOILER ALERT

Advent of Code, day 12 - 2022

At least, I am using terminedia for something
beyond the 2D vectors -

"""

import terminedia as TM

# And I found a bug - vectors derived from "TM.Directions" will raise on repr 
# monkeypatch
TM.utils.vector.NamedV2.__repr__ = lambda s: f"({s.x,s.y})"

gg = TM.ColorGradient([(0, (0,0, 255)), (0.1, (0, 255, 64)), (0.8, (0,128,0)), (0.9, (255,0,0))])
g2 = TM.ColorGradient([(0, (0,0,0)), (1, (255,255,255))])

arrows = {
    (0, -1): '🡡',
    (0, 1): '🡣',
    (1, 0): '🡢',
    (-1, 0): '🡠'
}
arrows = {
    (0, -1): '🡑',
    (0, 1): '🡓',
    (1, 0): '🡒',
    (-1, 0): '🡐'
}

def display(sc, map_, gradient, g2):
    shape = sc.shape
    for y in range(map_.height):
        for x in range(map_.width):
            dist, from_dir = map_.pathlayer.get((x, y), (255, "."))
            arrow = arrows.get(from_dir, from_dir)
            shape[x,y] = (arrow, g2[dist / 255], gradient[map_[x,y] / 27], 0)
    shape[map_.start] = ("S", (255,255, 0), TM.TRANSPARENT, 0)
    shape[map_.end] = ("E", (255,255,0), TM.TRANSPARENT, 0)
    sc.update()


class Map:
    def __init__(self, data, strategy="up"):
        self.strategy = strategy
        self.load(data)
        self.reset()

    def reset(self):
        self.pathlayer = {}
        self.paths = {}

    def run(self):
        self.reset()
        current_paths = {(0, (self.start if self.strategy == "up" else self.end), "S")}
        count = 0
        while current_paths:
            next_paths = set()
            for distance, pos, from_dir in current_paths:
                count += 1
                if not count % 100:
                    print(count)
                if distance < self.pathlayer.get(pos, (1_000_000, "."))[0]:
                    self.pathlayer[pos] = (distance, from_dir)
                else:
                    continue
                for direction in TM.Directions:
                    new_pos = pos + direction
                    # print(new_pos)
                    if not (0 <= new_pos.x < self.width) or not (0 <= new_pos.y < self.height):
                        continue
                    if self.strategy == "up":
                        if self[new_pos] > self[pos] + 1:
                            continue
                    elif self.strategy == "down":
                        if self[new_pos] < self[pos] - 1:
                            continue
                    else:
                        raise RuntimeError()
                    next_paths.add((distance + 1, new_pos, direction))
            current_paths = next_paths


    def load(self, data):
        self.data = []
        x = y = 0
        for y, line in enumerate(data.splitlines()):
            self.data.append(dline:=[])
            for x, char in enumerate(line):
                if char == "S":
                    self.start = (x, y)
                    char = "a"
                elif char == "E":
                    self.end = (x, y)
                    char = "z"
                height = ord(char) - ord("a")
                dline.append(height)
        self.width = x + 1
        self.height = y + 1


    def __getitem__(self, pos):
        return self.data[pos[1]][pos[0]]

    def __repr__(self):
        return "\n".join("".join(chr(char + 97)  for char in line) for line in self.data)

# part2
#m = Map(data, strategy="down")
#min(m.pathlayer.items(), key=lambda it: (m[it[0]], it[1][0]))

day12.png