[2022][day 24] add part 2 solution

2022/AOC24.py

@@ -54,12 +54,12 @@ def get_neighbors(pos) -> List[Point]:
  return neighbors
 
 
-def shortest_path(grid, blizzards_timelapse, start, end) -> int:
+def shortest_path(grid, blizzards_timelapse, start, end, start_time=0) -> int:
  """
  Returns shortest path to destination. Djikstra algorithm.
  """
  queue = []
- heapq.heappush(queue, (0, start))
+ heapq.heappush(queue, (start_time, start))
  visited = set()
 
  while queue:
@@ -69,13 +69,11 @@ def shortest_path(grid, blizzards_timelapse, start, end) -> int:
  else:
  visited.add((minutes, current_node))
 
- if minutes % 20 == 0:
- print(minutes, current_node)
  visited.add((minutes, current_node))
  current_blizzards = blizzards_timelapse[minutes]
 
  if current_node == end:
- return minutes - 1
+ return minutes - start_time - 1
 
  # try moving
  neighbors = get_neighbors(current_node)
@@ -128,9 +126,8 @@ def main(filename: str) -> Solution:
  grid, blizzards = process_input(filename)
 
  blizzards_timelapse = [blizzards]
+ # TODO find cycle
  for t in range(1000):
- # print(print_grid(blizzards))
- # print({k:v for k,v in blizzards.items() if v})
  new_blizzards = move_blizzards(grid, blizzards)
  blizzards_timelapse.append(new_blizzards)
  blizzards = new_blizzards
@@ -139,12 +136,17 @@ def main(filename: str) -> Solution:
  start = min(x for x, y in grid if y == 0), 0
  end = max(x for x, y in grid if y == max_y), max_y
 
- part_1_solution = shortest_path(grid, blizzards_timelapse, start, end)
- part_2_solution = 0
+ trip1 = shortest_path(grid, blizzards_timelapse, start, end)
+ trip2 = shortest_path(grid, blizzards_timelapse, end, start, start_time=trip1)
+ trip3 = shortest_path(
+ grid, blizzards_timelapse, start, end, start_time=trip1 + trip2
+ )
+ part_1_solution = trip1
+ part_2_solution = trip1 + trip2 + trip3
  return part_1_solution, part_2_solution
 
 
 if __name__ == "__main__":
  part_1_solution, part_2_solution = main("aoc24.txt")
  print(f"PART 1: {part_1_solution}") # 271
- print(f"PART 2: {part_2_solution}") #
+ print(f"PART 2: {part_2_solution}") # 813

2022/README.md

@@ -26,3 +26,4 @@ This repository contains Python solutions to the 2022 edition of [Advent of Code
 | [21](https://adventofcode.com/2022/day/21) | **Monkey Math** | [:star::star:](https://github.com/IAjimi/AdventOfCode/blob/master/2022/AOC21.py) | 
 | [22](https://adventofcode.com/2022/day/22) | **Monkey Map** | [:star::star:](https://github.com/IAjimi/AdventOfCode/blob/master/2022/AOC22.py) | 
 | [23](https://adventofcode.com/2022/day/23) | **Unstable Diffusion** | [:star::star:](https://github.com/IAjimi/AdventOfCode/blob/master/2022/AOC23.py) | 
+| [24](https://adventofcode.com/2022/day/24) | **Blizzard Basin** | [:star::star:](https://github.com/IAjimi/AdventOfCode/blob/master/2022/AOC24.py) |