Pat(Advanced Level)Practice--1006(Sign In and Sign Out)
Pat1006代码题目描述:Atthebeginningofeveryday,thefirstpersonwhosignsinthecomputerroomwillunlockthedoor,andthelastonewhosignsoutwilllockthedoor.Giventherecordsofsigningin'sandout's,youaresupposedtofindtheones