class GraphSearch:
"""
在python模拟图搜索模式
"""
def __init__(self, graph):
self.graph = graph
def find_path(self, start, end, path=None):
path = path or []
path.append(start)
if start == end:
return path
for node in self.graph.get(start, []):
if node not in path:
newpath = self.find_path(node, end, path)
if newpath:
return newpath
def find_all_path(self, start, end, path=None):
path = path or []
path.append(start)
if start == end:
return [path]
paths = []
for node in self.graph.get(start, []):
if node not in path:
newpaths = self.find_all_path(node, end, path[:])
paths.extend(newpaths)
return paths
def find_shortest_path(self, start, end, path=None):
path = path or []
path.append(start)
if start == end:
return path
shortest = None
for node in self.graph.get(start, []):
if node not in path:
newpath = self.find_shortest_path(node, end, path[:])
if newpath:
if not shortest or len(newpath) < len(shortest):
shortest = newpath
return shortest
#图用法的例子
graph = {'A': ['B', 'C'],
'B': ['C', 'D'],
'C': ['D'],
'D': ['C'],
'E': ['F'],
'F': ['C']
}
#新的图形搜索对象的初始化
graph1 = GraphSearch(graph)
print(graph1.find_path('A', 'D'))
print(graph1.find_all_path('A', 'D'))
print(graph1.find_shortest_path('A', 'D'))
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