advent-of-code/2024/13/two_clean.py
2024-12-25 12:59:49 +01:00

124 lines
3.5 KiB
Python

#!/usr/bin/env python3
import math
import re
import sys
input_file = sys.argv[1]
with open(input_file) as fd:
lines = [line.rstrip() for line in fd.readlines()]
coords = tuple[int, int]
prizes: list[coords] = list()
buttons: list[tuple[coords, coords]] = list()
for li, line in enumerate(lines):
machine = li // 4
offset = li % 4
if offset == 0:
match = re.match(r"^Button A: X\+([0-9]+), Y\+([0-9]+)$", line)
assert match
button_a = int(match[1]), int(match[2])
elif offset == 1:
match = re.match(r"^Button B: X\+([0-9]+), Y\+([0-9]+)$", line)
assert match
button_b = int(match[1]), int(match[2])
buttons.append((button_a, button_b))
elif offset == 2:
match = re.match("^Prize: X=([0-9]+), Y=([0-9]+)$", line)
assert match
prize = int(match[1]), int(match[2])
# prize = prize[0] + 10000000000000, prize[1] + 10000000000000
prizes.append(prize)
assert len(prizes) == len(buttons)
def slope(point: coords) -> float:
return point[1] / point[0]
def norm(point: coords) -> float:
return math.sqrt(math.pow(point[1], 2) + math.pow(point[0], 2))
ttoks = 0
token_a, token_b = 3, 1
for arcade, prize in enumerate(prizes):
butts = buttons[arcade]
button_a, button_b = butts
print(43, prize, button_a, button_b)
toks = None
max_a_x = int(math.ceil(prize[0] / button_a[0]))
max_a_y = int(math.ceil(prize[1] / button_a[1]))
max_a = min(max_a_x, max_a_y)
max_b_x = int(math.ceil(prize[0] / button_b[0]))
max_b_y = int(math.ceil(prize[1] / button_b[1]))
max_b = min(max_b_x, max_b_y)
slope_a = slope(button_a)
slope_b = slope(button_b)
slope_prize = slope(prize)
slope_but_min = min(slope_a, slope_b)
slope_but_max = max(slope_a, slope_b)
if slope_prize < slope_but_min or slope_prize > slope_but_max:
print("Not in range")
continue
norm_a = norm(button_a)
norm_b = norm(button_b)
speed_a = norm_a / 3
speed_b = norm_b / 1
if speed_a > speed_b:
button_fastest, button_slowest = button_a, button_b
token_fastest, token_slowest = token_a, token_b
max_fastest = max_a
else:
button_fastest, button_slowest = button_b, button_a
token_fastest, token_slowest = token_b, token_a
max_fastest = max_b
toks = 0
min_presses_fastest = 0
max_presses_fastest = max_fastest
while min_presses_fastest + 1 < max_presses_fastest:
presses_fastest = int(
math.floor((min_presses_fastest + max_presses_fastest) / 2)
)
pri_x, pri_y = (
prize[0] - button_fastest[0] * presses_fastest,
prize[1] - button_fastest[1] * presses_fastest,
)
slope_pri = slope((pri_x, pri_y))
if slope_pri >= slope_but_min and slope_pri <= slope_but_max:
min_presses_fastest = presses_fastest
else:
max_presses_fastest = presses_fastest
presses_fastest = max_presses_fastest
pri_x, pri_y = (
prize[0] - button_fastest[0] * presses_fastest,
prize[1] - button_fastest[1] * presses_fastest,
)
pri_x += button_fastest[0]
pri_y += button_fastest[1]
toks = presses_fastest * token_fastest
toks -= token_fastest
presses_slowest, remainder = divmod(pri_x, button_slowest[0])
if remainder == 0 and (pri_y == presses_slowest * button_slowest[1]):
toks += presses_slowest * token_slowest
else:
toks = None
print(76, toks)
if toks is not None:
ttoks += toks
print(ttoks)