Codeforces Round #628 (Div. 2) F. Ehab's Last Theorem(详解)
F.Ehab'sLastTheoremIt'stheyear5555.Youhaveagraph,andyouwanttofindalongcycleandahugeindependentset,justbecauseyoucan.Butfornow,let'sjuststickwithfindingeither.Givenaconnectedgraphwithnnvertices,youcanc