采用狄克斯特拉求带权有向图的最短路径代码

狄克斯特拉算法（Dijkstra's Algorithm）是一种用于解决单源最短路径问题的贪心算法，特别适用于加权有向图。以下是用Python实现的一个基本版本：

import heapq

def dijkstra(graph, start):
    distances = {node: float('infinity') for node in graph}
    distances[start] = 0
    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))
                
    return distances

# 示例：假设graph是一个字典，键是节点，值是邻接字典，表示有向边及其权重
graph = {
    'A': {'B': 5, 'C': 1},
    'B': {'A': 5, 'C': 2, 'D': 1},
    'C': {'A': 1, 'B': 2, 'D': 4},
    'D': {'B': 1, 'C': 4}
}

shortest_paths = dijkstra(graph, 'A')
print("从'A'到其他节点的最短路径:", shortest_paths)