2018hdu杭电多校第八场 hdu6397 Character Encoding(组合数+容斥定理/生成函数(母函数))
CharacterEncodingTimeLimit:2000/1000MS(Java/Others)MemoryLimit:131072/131072K(Java/Others)TotalSubmission(s):922AcceptedSubmission(s):357ProblemDescriptionIncomputerscience,acharacterisaletter,adigit,