dexHeadNULL借阅信息头指针BorrowpBorrowHeadNULL用来保存当前用户的输入i
tChoosedNum1whiletrue
ChoosedNumShowMai
Me
uswitchChoosedNumcase0退出
retur
0breakcase1图书入库PutBookI
LibpBookHeadpI
dexHeadbreakcase2查询库存
f13
QueryBookLibpBookHeadpri
tf