如果使用最大优先级队列，Dijkstra算法是如何工作的？

import heapq

def dijkstra(graph, start):
    queue = []
    distances = {node: float('inf') for node in graph}
    distances[start] = 0
    heapq.heappush(queue, (0, start))

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

        if current_distance > distances[current_node]:
            continue

        for neighbor, weight in graph[current_node].items():
            distance = current_distance + weight

            if distance < distances[neighbor]:
                distances[neighbor] = distance
                heapq.heappush(queue, (-distance, neighbor))  # 使用负值实现最大优先级队列

    return distances

# 示例图
graph = {
    'A': {'B': 1, 'C': 4},
    'B': {'A': 1, 'C': 2, 'D': 5},
    'C': {'A': 4, 'B': 2, 'D': 1},
    'D': {'B': 5, 'C': 1}
}

print(dijkstra(graph, 'A'))