本文实例讲述了python数据结构之图的实现方法。分享给大家供大家参考。具体如下：
下面简要的介绍下：
比如有这么一张图：
A -> B
A -> C
B -> C
B -> D
C -> D
D -> C
E -> F
F -> C
可以用字典和列表来构建
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graph = {'A': ['B', 'C'], 'B': ['C', 'D'], 'C': ['D'], 'D': ['C'], 'E': ['F'], 'F': ['C']} |
找到一条路径：
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def find_path(graph, start, end, path=[]): path = path + [start] if start == end: return path if not graph.has_key(start): return None for node in graph[start]: if node not in path: newpath = find_path(graph, node, end, path) if newpath: return newpath return None |
找到所有路径：
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def find_all_paths(graph, start, end, path=[]): path = path + [start] if start == end: return [path] if not graph.has_key(start): return [] paths = [] for node in graph[start]: if node not in path: newpaths = find_all_paths(graph, node, end, path) for newpath in newpaths: paths.append(newpath) return paths |
找到最短路径：
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def find_shortest_path(graph, start, end, path=[]): path = path + [start] if start == end: return path if not graph.has_key(start): return None shortest = None for node in graph[start]: if node not in path: newpath = find_shortest_path(graph, node, end, path) if newpath: if not shortest or len(newpath) < len(shortest): shortest = newpath return shortest |
希望本文所述对大家的Python程序设计有所帮助。
