用python编程在10个顶点的无向图中,每对顶点之间以概率0.6存在一条权重为[1,10]上随机整数的边,首先生成该图。然后求解下列问题:(2)求顶点v1到顶点v10的最短距离和最短路径。分别用Prim和Kruskal算法实现
时间: 2024-03-23 08:40:34 浏览: 92
好的,针对你的问题,我可以为你提供以下Python代码实现,其中用到了networkx库和heapq库:
```python
import random
import networkx as nx
import heapq
# 生成无向图
G = nx.Graph()
for i in range(1, 11):
for j in range(i+1, 11):
if random.random() <= 0.6:
weight = random.randint(1, 10)
G.add_edge(i, j, weight=weight)
# Prim算法实现最短距离和最短路径
def prim(G, start):
visited = set([start])
candidate_edges = [(weight, start, to) for to, weight in G[start].items()]
heapq.heapify(candidate_edges)
mst = []
total_weight = 0
while candidate_edges:
weight, frm, to = heapq.heappop(candidate_edges)
if to not in visited:
visited.add(to)
mst.append((frm, to))
total_weight += weight
for to_next, weight in G[to].items():
if to_next not in visited:
heapq.heappush(candidate_edges, (weight, to, to_next))
return mst, total_weight
mst_prim, weight_prim = prim(G, 1)
print("Prim算法求解:")
print("最短距离:", nx.shortest_path_length(G, source=1, target=10, weight='weight'))
print("最短路径:", nx.shortest_path(G, source=1, target=10, weight='weight'))
print("Prim算法求得的最小生成树边集:", mst_prim)
print("Prim算法求得的最小生成树权重:", weight_prim)
# Kruskal算法实现最短距离和最短路径
def kruskal(G):
edges = [(G[u][v]['weight'], u, v) for u, v in G.edges()]
edges.sort()
mst = []
total_weight = 0
uf = {u:u for u in G.nodes()}
for weight, u, v in edges:
if uf[u] != uf[v]:
mst.append((u, v))
total_weight += weight
old = uf[u]
new = uf[v]
for w, k in uf.items():
if k == old:
uf[w] = new
return mst, total_weight
mst_kruskal, weight_kruskal = kruskal(G)
print("Kruskal算法求解:")
print("最短距离:", nx.shortest_path_length(G, source=1, target=10, weight='weight'))
print("最短路径:", nx.shortest_path(G, source=1, target=10, weight='weight'))
print("Kruskal算法求得的最小生成树边集:", mst_kruskal)
print("Kruskal算法求得的最小生成树权重:", weight_kruskal)
```
解释一下代码的思路:首先使用networkx库生成一个10个节点的空图,然后遍历所有节点对,以0.6的概率添加一条边,边的权重在[1,10]之间随机生成。接下来,使用Prim算法和Kruskal算法分别求出该图的最小生成树,并输出最小生成树的边集和权重。最后,使用networkx库提供的`shortest_path_length`和`shortest_path`函数求出顶点v1到顶点v10的最短距离和最短路径,并输出结果。
希望这个代码可以帮助到你!
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