The homeomorphism classification of graph like manifolds can be transformed into a 2 edge colouring enumeration problem for graphs.

图式流形的同胚分类可转化为图的一类2 -边着色计数问题。

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R-colouring is only used by the people in Northern China. Almost every Chinese in Southern China, like me, never use it, while there is still no problem in communication.

其实儿话音只是中国北方人说的，像我这样的南方人从来不用儿话音，交流也没问题。

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