algo/python/31_bfs_dfs/graph_application.py

46 lines
1.0 KiB
Python

# -*- coding:utf-8 -*-
from collections import deque
from graph import Undigraph
def find_vertex_by_degree(graph, s, degree):
if len(graph) <= 1:
return []
if degree == 0:
return [s]
d_vertices = []
queue = deque()
prev = [-1] * len(graph)
visited = [False] * len(graph)
visited[s] = True
queue.append(s)
while len(queue) > 0:
sz = len(queue)
for i in range(sz):
v = queue.popleft()
for adj_v in graph[v]:
if not visited[adj_v]:
prev[adj_v] = v
visited[adj_v] = True
queue.append(adj_v)
degree -= 1
if degree == 0 and len(queue) != 0:
return queue
if __name__ == '__main__':
g = Undigraph(8)
g.add_edge(0, 1)
g.add_edge(0, 3)
g.add_edge(1, 2)
g.add_edge(1, 4)
g.add_edge(2, 5)
g.add_edge(3, 4)
g.add_edge(4, 5)
g.add_edge(4, 6)
g.add_edge(5, 7)
g.add_edge(6, 7)
print(find_vertex_by_degree(g, 0, 4))