import heapq import copy # 定义状态类 class State: def __init__(self, board, moves=0, parent=None, last_move=None): self.board = board self.moves = moves self.parent = parent self.last_move = last_move def __lt__(self, other): return self.moves < other.moves def __eq__(self, other): return self.board == other.board # 定义转移函数 def move(state, direction): new_board = copy.deepcopy(state.board) for i in range(len(new_board)): if 0 in new_board[i]: j = new_board[i].index(0) break if direction == "up": if i == 0: return None else: new_board[i][j], new_board[i-1][j] = new_board[i-1][j], new_board[i][j] elif direction == "down": if i == len(new_board)-1: return None else: new_board[i][j], new_board[i+1][j] = new_board[i+1][j], new_board[i][j] elif direction == "left": if j == 0: return None else: new_board[i][j], new_board[i][j-1] = new_board[i][j-1], new_board[i][j] elif direction == "right": if j == len(new_board)-1: return None else: new_board[i][j], new_board[i][j+1] = new_board[i][j+1], new_board[i][j] return State(new_board, state.moves+1, state, direction) # 定义A*算法 def astar(start, goal): heap = [] closed = set() heapq.heappush(heap, start) while heap: state = heapq.heappop(heap) if state.board == goal: path = [] while state.parent: path.append(state) state = state.parent path.append(state) return path[::-1] closed.add(state) for direction in ["up", "down", "left", "right"]: child = move(state, direction) if child is None: continue if child in closed: continue if child not in heap: heapq.heappush(heap, child) else: for i, (p, c) in enumerate(heap): if c == child and p.moves > child.moves: heap[i] = (child, child) heapq.heapify(heap) # 测试 start_board = [[1, 2, 3], [4, 5, 6], [7, 8, 0]] goal_board = [[2, 3, 6], [1, 5, 8], [4, 7, 0]] start_state = State(start_board) goal_state = State(goal_board) path = astar(start_state, goal_board) for state in path: print(state.board)
时间: 2023-06-01 10:01:32 浏览: 159
校园导游路线最近计算.zip_shortest path graph_路线计算
import heapq 是 Python 中用于实现堆数据结构的模块,可以用于排序和优先队列等场景。而 import copy 则是 Python 中用于复制对象的模块,可以使用 deepcopy 和 shallowcopy 等方法来实现深拷贝和浅拷贝。
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