以下是一个示例代码,用于按最短路径排序并不排除断开的节点:
import heapq
def shortest_path(graph, start):
# 初始化距离字典和前驱节点字典
distances = {node: float('inf') for node in graph}
distances[start] = 0
previous_nodes = {node: None for node in graph}
# 使用堆优化的Dijkstra算法计算最短路径
heap = [(0, start)]
while heap:
current_distance, current_node = heapq.heappop(heap)
# 跳过已经处理过的节点
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
# 更新距离和前驱节点
if distance < distances[neighbor]:
distances[neighbor] = distance
previous_nodes[neighbor] = current_node
heapq.heappush(heap, (distance, neighbor))
return distances, previous_nodes
def sort_by_shortest_path(graph, start):
# 调用最短路径函数获取距离字典和前驱节点字典
distances, previous_nodes = shortest_path(graph, start)
# 按距离排序节点
sorted_nodes = sorted(distances.keys(), key=lambda x: distances[x])
return sorted_nodes
# 测试示例
graph = {
'A': {'B': 5, 'C': 2},
'B': {'A': 5, 'D': 1},
'C': {'A': 2, 'D': 6},
'D': {'B': 1, 'C': 6}
}
start_node = 'A'
sorted_nodes = sort_by_shortest_path(graph, start_node)
print(sorted_nodes)
输出结果为:['A', 'C', 'B', 'D']
,表示按最短路径排序的节点顺序。
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