我是在節點a和b之間遍歷的dfs,但是當我在節點b處打開循環時,算法會繼續。這裏是我的代碼:如何在不返回或中斷Python的情況下實現函數
import networkx as nx
def Graph():
G=nx.Graph()
k = 30
G.add_edge(1,2)
G.add_edge(2,3)
G.add_edge(1,3)
for i in range(2,k+1):
G.add_edge(2*i-2,2*i)
G.add_edge(2*i-1,2*i)
G.add_edge(2*i-1,2*i+1)
G.add_edge(2*i,2*i+1)
G.add_nodes_from(G.nodes(), color='never coloured')
G.add_nodes_from(G.nodes(), label = -1)
G.add_nodes_from(G.nodes(), visited = 'no')
return G
def dfs(G,a,b,u):
global i
G.node[u]['visited'] = 'yes'
i += 1
G.node[u]['label'] = i
print(u)
print("i", i)
for v in G.neighbors(u):
if v == b:
G.node[v]['visited'] = 'yes'
i += 1
G.node[v]['label'] = i
print("b is ", v)
print("distance from a to b is ", G.node[v]['label'])
break### the problem area, doesn't break out the function
elif v != b:
if G.node[v]['visited'] == 'no':
dfs(G,a,b,v)
G=Graph()
a=1
b=19
i = 0
print('Depth-First-Search visited the following nodes of G in this order:')
dfs(G,a,b,a) ### count the DFS-path from a to b, starting at a
print('Depth-First Search found in G7 a path between vertices', a, 'and', b, 'of length:', G7.node[b]['label'])
print()
我已經嘗試返回for循環,嘗試使用中斷,也試過try/catch方法。有沒有優雅的方式來打破這個功能,或者我將不得不重寫它,因爲它不通過你的所有鄰居遞解?