111 lines
2.4 KiB
Python
111 lines
2.4 KiB
Python
import sys
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sys.path.append('../aoclib')
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from aoclib import Input
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import heapq
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sys.setrecursionlimit(15000)
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L = '<'
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U = '^'
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R = '>'
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D = 'v'
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EMPTY = '.'
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WALL = '#'
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START = 'S'
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END = 'E'
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class Maze:
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def __init__(self, lines: list[list[str]]):
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self.grid = lines
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for y in range(len(self.grid)):
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for x in range(len(self.grid[0])):
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if self.grid[y][x] == START:
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self.s = (x, y)
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elif self.grid[y][x] == END:
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self.e = (x, y)
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def __str__(self):
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grid = [r.copy() for r in self.grid]
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return '\n'.join(''.join(row) for row in grid)
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def start(self) -> tuple[int, int]:
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return self.s
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def end(self, pos: tuple[int, int]) -> bool:
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return self.e == pos
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def is_wall(self, pos) -> bool:
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x, y = pos
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return self.grid[y][x] == WALL
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def search(m: Maze) -> int:
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x, y = m.start()
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state = (x, y, 1, 0) # x diff is 1 (we are facing right), y diff is 0
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queue = []
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visited = set()
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heapq.heappush(queue, (0, state))
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visited.add(state)
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while queue:
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cost, state = heapq.heappop(queue)
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x, y, xd, yd = state
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if m.end((x, y)):
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return cost
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options = [
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# move forward
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(cost+1, (x+xd, y+yd, xd, yd)),
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# turn
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(cost+1000, (x, y, -yd, xd)),
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(cost+1000, (x, y, yd, -xd)),
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]
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for opt in options:
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cost, state = opt
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x, y, _, _ = state
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if m.is_wall((x, y)):
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continue
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if state in visited:
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continue
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visited.add(state)
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heapq.heappush(queue, (cost, state))
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return -1
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def solve1(lines: list[list[str]]):
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m = Maze(lines)
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res = search(m)
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return res
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def solve2(lines: list[list[str]]):
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maze = Maze(lines)
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return ''
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if __name__ == '__main__':
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lines = Input('input_test.txt').lines_as_lists()
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#part 1
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print('test part 1:', solve1(lines))
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#part 2
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print('test part 2:', solve2(lines))
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lines = Input('input_test2.txt').lines_as_lists()
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#part 1
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print('test 2 part 1:', solve1(lines))
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#part 2
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print('test 2 part 2:', solve2(lines))
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lines = Input('input.txt').lines_as_lists()
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#part 1
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print('part 1:', solve1(lines)) # 90460
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#part 2
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print('part 2:', solve2(lines))
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