131 lines
3.3 KiB
Python
131 lines
3.3 KiB
Python
from collections import deque
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from pprint import pprint
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NORTH = 1
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EAST = 2
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SOUTH = 4
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WEST = 8
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ROOT = 0
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IN_PARENS = 1
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SKIPPING = 2
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start_pos = 200, 200
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grid = [[0] * start_pos[0] * 2 for _ in range(start_pos[1] * 2)]
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min_x, max_x = start_pos
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min_y, max_y = start_pos
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def print_grid(x_=None, y_=None):
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for y in range(min_y, max_y + 1):
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for x in range(min_x, max_x + 1):
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print(end="@")
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print(end="-" if grid[y][x] & NORTH else "@")
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print("#")
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for x in range(min_x, max_x + 1):
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print(end="|" if grid[y][x] & WEST else "@")
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if (x, y) == start_pos:
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print(end="X")
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elif x == x_ and y == y_:
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print(end=".")
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else:
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print(end=" ")
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print("@")
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print("@" * ((max_x - min_x) * 2 + 3))
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def parse_input(inp):
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global min_x, max_x, min_y, max_y
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# print(inp, end="\n\n")
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# print("\033[2J\033[;H")
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stack = [(0, start_pos[0], start_pos[1])]
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while stack:
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# print("===================================")
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# print(stack, end=" -> ")
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start, x, y = stack.pop()
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# print(start)
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depth = 0
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skip_to_end = False
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for i in range(start, len(inp)):
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c = inp[i]
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if depth == 0 and not skip_to_end:
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# print(f"{depth} {inp[:i]}\033[4;3{depth+1}m{inp[i]}\033[0m{inp[i+1:]} ({x:>2},{y:>2}) -> ", end="")
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if c == "N": grid[y][x] |= NORTH; y -= 1; grid[y][x] |= SOUTH
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elif c == "E": grid[y][x] |= EAST; x += 1; grid[y][x] |= WEST
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elif c == "S": grid[y][x] |= SOUTH; y += 1; grid[y][x] |= NORTH
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elif c == "W": grid[y][x] |= WEST; x -= 1; grid[y][x] |= EAST
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if x < min_x: min_x = x
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if x > max_x: max_x = x
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if y < min_y: min_y = y
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if y > max_y: max_y = y
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# print(f"({x:>2},{y:>2})")
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# print_grid(x, y)
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# print()
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if c == "(" and not skip_to_end:
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if depth == 0:
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stack.append((i + 1, x, y))
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depth += 1
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elif c == "|" and not skip_to_end:
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if depth == 1:
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stack.append((i + 1, x, y))
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elif depth == 0:
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skip_to_end = True
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elif c == ")":
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depth -= 1
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if depth == -1:
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skip_to_end = False
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break
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# print()
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# print("\033[0;0H", end="")
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# print_grid()
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def bfs():
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pos = start_pos
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queue = deque([(pos, 0)])
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seen = set()
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lengths = []
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max_len = 0
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long_paths = 0
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while queue:
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(x, y), depth = queue.popleft()
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if (x, y) in seen:
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continue
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seen.add((x, y))
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if depth > max_len:
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max_len = depth
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if depth >= 1000:
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long_paths += 1
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if grid[y][x] & WEST: queue.append(((x - 1, y), depth + 1))
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if grid[y][x] & EAST: queue.append(((x + 1, y), depth + 1))
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if grid[y][x] & NORTH: queue.append(((x, y - 1), depth + 1))
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if grid[y][x] & SOUTH: queue.append(((x, y + 1), depth + 1))
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print("part 1:", max_len)
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print("part 2:", long_paths)
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def main():
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inp = input()
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parse_input(inp[1:-1])
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bfs()
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main()
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