2018-12-29 19:30:21 +08:00
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#coding: utf-8
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''' mbinary
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#######################################################################
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# File : isBipartGraph.py
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# Author: mbinary
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# Mail: zhuheqin1@gmail.com
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2019-01-31 12:09:46 +08:00
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# Blog: https://mbinary.xyz
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2018-12-29 19:30:21 +08:00
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# Github: https://github.com/mbinary
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# Created Time: 2018-12-21 15:00
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# Description: Judge if a graph is bipartite
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The theorical idea is to judge whether the graph has a odd-path circle. However, it's hard to implement.
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The following codes show a method that colors the nodes by dfs.
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#######################################################################
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'''
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def isBipartite(self, graph):
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"""
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:type graph: List[List[int]]
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:rtype: bool
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"""
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n = len(graph)
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self.node = graph
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self.color = {i:None for i in range(n)}
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return all(self.dfs(i,True) for i in range(n) if self.color[i] is None)
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def dfs(self,n,col=True):
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if self.color[n] is None:
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self.color[n]=col
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return all(self.dfs(i,not col) for i in self.node[n])
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else:return col==self.color[n]
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