TransitiveClosure

http://acm.nudt.edu.cn/~twcourse/TransitiveClosure.html

https://en.wikipedia.org/wiki/Closure_(mathematics)#P_closures_of_binary_relations

http://cs.winona.edu/lin/cs440/ch08-2.pdf

https://en.wikipedia.org/wiki/Closure_(mathematics)#P_closures_of_binary_relations

http://files.cnblogs.com/files/WCFGROUP/OptimizingCompilersforModernArchitectures.pdf

http://files.cnblogs.com/files/WCFGROUP/EngineeringaCompilerSecondEdition.pdf

http://files.cnblogs.com/files/WCFGROUP/CompilersPrinciplesTechniquesandTools2nd.pdf

http://files.cnblogs.com/files/WCFGROUP/ModernCompilerDesign2Ed.pdf

http://files.cnblogs.com/files/WCFGROUP/ModernCompilerImplementationinJava.pdf