对Dijkstra算法进行编码而无需修改原始节点

import heapq

def dijkstra(graph, start):
    # 初始化距离字典，将起始节点的距离设为0，其他节点的距离设为无穷大
    distances = {node: float('inf') for node in graph}
    distances[start] = 0

    # 使用优先队列来存储节点和对应的距离
    queue = [(0, start)]

    while queue:
        current_distance, current_node = heapq.heappop(queue)

        # 如果当前节点已经被访问过，则跳过
        if current_distance > distances[current_node]:
            continue

        # 遍历当前节点的邻居节点
        for neighbor, weight in graph[current_node].items():
            distance = current_distance + weight

            # 如果通过当前节点到达邻居节点的距离更短，则更新距离字典和优先队列
            if distance < distances[neighbor]:
                distances[neighbor] = distance
                heapq.heappush(queue, (distance, neighbor))

    return distances