From 3b4efce02f1d4fe97c9f694abecf7e17a7f05aff Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mika=C3=ABl=20Capelle?= Date: Sun, 18 Dec 2022 16:46:00 +0100 Subject: [PATCH] Clean day 17. --- 2022/day17.py | 61 +++++++++++--------------------------------- 2022/tests/day17.txt | 1 + 2022/tests/day18.txt | 13 ++++++++++ 3 files changed, 29 insertions(+), 46 deletions(-) create mode 100644 2022/tests/day17.txt create mode 100644 2022/tests/day18.txt diff --git a/2022/day17.py b/2022/day17.py index 7fc07d3..200ed99 100644 --- a/2022/day17.py +++ b/2022/day17.py @@ -1,31 +1,5 @@ # -*- encoding: utf-8 -*- -""" -Part 2: - The idea is to find a repeatable tower to not have to calculate up to the given - number. - - The issue here is that you can consume a variable number of jets per rock, so you - cannot simply build a tower of hight LCM(len(ROCKS), len(JETS)), you need to find - a repeat point. The easiest repeat point is one where the incoming rock is the - first one (horizontal line) at the same place in the jet sequence. - - The first rock cannot pass any rock present in the tower, so we know if we start - with the same sequence of jets, it will end at the exact same positions (bottom) - and following rocks will follow the same pattern. - - What I did: - 1. Place rocks as in part 1 but keep tracks of the (rock 0, jet) previously done - (where jet is the index in the sequence, not just '<' or '>'). When a - (rock 0, jet) pair gets repeats, stop the process. - 2. At this points, you have places N rocks and the number of rocks between the - two (rock 0, jet) points is K. You have 1000... - N rocks to place, and you - can repeat sequence of K blocks by building towers of hight K starting with - rock 0 and at position "jet" in the sequence of jets. - 3. Once this is done, you are left with (1000... - N) % K rocks to place, starting - again at index "jet" in the sequence of jets. -""" - import sys from typing import Sequence, TypeVar @@ -45,7 +19,7 @@ def print_tower(tower: np.ndarray, out: str = "#"): print("+" + "-" * tower.shape[1] + "+") -def tower_hight(tower: np.ndarray) -> int: +def tower_height(tower: np.ndarray) -> int: return int(tower.shape[0] - tower[::-1, :].argmax(axis=0).min() - 1) @@ -74,12 +48,13 @@ def build_tower( jets: str, early_stop: bool = False, init: np.ndarray = np.ones(WIDTH, dtype=bool), -) -> tuple[np.ndarray, int, tuple[int, int], int]: +) -> tuple[np.ndarray, int, int, dict[int, int]]: tower = EMPTY_BLOCKS.copy() tower[0, :] = init done_at: dict[tuple[int, int], int] = {} + heights: dict[int, int] = {} i_jet, i_rock = 0, 0 rock_count = 0 @@ -119,38 +94,32 @@ def build_tower( rock_y += 1 break + heights[rock_count] = tower_height(tower) tower[rock_y, rock_x] = True - return tower, rock_count, (i_rock, i_jet), done_at.get((i_rock, i_jet), -1) + return tower, rock_count, done_at.get((i_rock, i_jet), -1), heights line = sys.stdin.read().strip() tower, *_ = build_tower(2022, line) -answer_1 = tower_hight(tower) +answer_1 = tower_height(tower) print(f"answer 1 is {answer_1}") TOTAL_ROCKS = 1_000_000_000_000 -tower_1, n_rocks_1, (i_rocks_1, i_jet_1), prev_1 = build_tower(TOTAL_ROCKS, line, True) +tower_1, n_rocks_1, prev_1, heights_1 = build_tower(TOTAL_ROCKS, line, True) +assert prev_1 > 0 -# shift the line -line = line[i_jet_1:] + line[:i_jet_1] - -# remaining rocks +# 2767 1513 remaining_rocks = TOTAL_ROCKS - n_rocks_1 n_repeat_rocks = n_rocks_1 - prev_1 - -# repeated tower n_repeat_towers = remaining_rocks // n_repeat_rocks -tower_repeat, *_ = build_tower(n_repeat_rocks, line) -# remaining tower -remaining_rocks = remaining_rocks % n_repeat_rocks -tower_remaining, *_ = build_tower(remaining_rocks, line) - -answer_2 = ( - tower_hight(tower_1) - + tower_hight(tower_repeat) * n_repeat_towers - + tower_hight(tower_remaining) +base_height = heights_1[prev_1] +repeat_height = heights_1[prev_1 + n_repeat_rocks - 1] - heights_1[prev_1] +remaining_height = ( + heights_1[prev_1 + remaining_rocks % n_repeat_rocks] - heights_1[prev_1] ) + +answer_2 = base_height + (n_repeat_towers + 1) * repeat_height + remaining_height print(f"answer 2 is {answer_2}") diff --git a/2022/tests/day17.txt b/2022/tests/day17.txt new file mode 100644 index 0000000..97a1aa1 --- /dev/null +++ b/2022/tests/day17.txt @@ -0,0 +1 @@ +>>><<><>><<<>><>>><<<>>><<<><<<>><>><<>> diff --git a/2022/tests/day18.txt b/2022/tests/day18.txt new file mode 100644 index 0000000..73a7202 --- /dev/null +++ b/2022/tests/day18.txt @@ -0,0 +1,13 @@ +2,2,2 +1,2,2 +3,2,2 +2,1,2 +2,3,2 +2,2,1 +2,2,3 +2,2,4 +2,2,6 +1,2,5 +3,2,5 +2,1,5 +2,3,5