forked from UNN/2026-rff_mp
54 lines
1.8 KiB
Python
54 lines
1.8 KiB
Python
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from collections import deque
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from typing import List, Dict
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from .path_finding_strategy import PathFindingStrategy
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class BFSStrategy(PathFindingStrategy):
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"""Поиск в ширину (BFS) - гарантирует кратчайший путь"""
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def __init__(self):
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self._visited_count = 0
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@property
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def name(self) -> str:
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return "BFS"
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def find_path(self, maze, start, exit_cell) -> List:
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"""Находит путь с помощью BFS"""
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if not start or not exit_cell:
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return []
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# Очередь для BFS
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queue = deque([start])
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# Множество посещенных клеток
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visited = {start}
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# Словарь для восстановления пути
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parent = {start: None}
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self._visited_count = 0
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while queue:
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current = queue.popleft()
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self._visited_count += 1
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# Нашли выход
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if current == exit_cell:
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return self._reconstruct_path(parent, exit_cell)
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# Проверяем всех соседей
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for neighbor in maze.get_neighbors(current):
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if neighbor not in visited:
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visited.add(neighbor)
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parent[neighbor] = current
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queue.append(neighbor)
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# Путь не найден
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return []
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def _reconstruct_path(self, parent: Dict, end) -> List:
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"""Восстанавливает путь от终点 до старта"""
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path = []
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current = end
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while current is not None:
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path.append(current)
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current = parent.get(current)
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return list(reversed(path))
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