说明

代码

import heapq
def dijkstra(graph, start):
    distances = {node: float('inf') for node in graph}
    distances[start] = 0
    queue = [(0, start)]
    while queue:
        current_distance, current_node = heapq.heappop(queue)
        if distances[current_node] < current_distance:
            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

graph = { #图
    's':{'t':10,'y':5},
    't':{'y':2,'x':1},
    'y':{'t':3,'x':9,'z':2},
    'x':{'z':4},
    'z':{'s':7,'x':6}
} 
print(dijkstra(graph, 's'))  # 输出: {'A': 0, 'B': 1, 'C': 3, 'D': 4}