57 lines
1.7 KiB
Python
57 lines
1.7 KiB
Python
from heapq import *
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from source.strategy import PathFindingStrategy, reconstruct_path
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from source.classes import Maze, Cell
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class Dijkstra(PathFindingStrategy):
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@property
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def name(self) -> str:
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"""Возвращает название метода"""
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return "Dijkstra"
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def findPath(self, maze: Maze):
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start_cell = maze.start
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exit_cell = maze.exit
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queue = []
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counter = 0 # счётчик для уникальности, чтобы не сравнивать клетки
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heappush(queue, (0, counter, start_cell))
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counter += 1
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cost_visited = {start_cell.getXY(): 0}
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came_from = {start_cell.getXY(): None}
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visited_count = 1
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while queue:
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current_cost, _, current_cell = heappop(queue)
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if current_cell.getXY() == exit_cell.getXY():
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return reconstruct_path(
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came_from=came_from,
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start=start_cell,
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end=current_cell
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), visited_count
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next_cells = maze.getNeighbors(current_cell)
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for next_cell in next_cells:
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neighbor_cost = next_cell.value
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neighbor_cell_xy = next_cell.getXY()
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new_cost = current_cost + neighbor_cost
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if neighbor_cell_xy not in cost_visited or new_cost < cost_visited[neighbor_cell_xy]:
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heappush(queue, (new_cost, counter, next_cell))
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counter += 1
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cost_visited[neighbor_cell_xy] = new_cost
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came_from[neighbor_cell_xy] = current_cell
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visited_count += 1
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return [], visited_count
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