i
sertstructstude
theadstructstude
tstudstud是添加的用户structstude
tp0p1p2p1headp0studifheadNULL如果没有任何用户添加为第一表尾
headp0p0
extNULLelsewhilep0
ump1
ump1
extNULL按号码小到大排列并寻找添加节点p2p1p1p1
extifp0
ump1
umifheadp1headp0elsep2
extp0p0
extp1elsep1
extp0p0
extNULL在末尾恰好最小在中间p1将指向下一个节点
f
1retur
head
添加后接点数
structstude
tdelstructstude
theadlo
g
umstructstude
tp1p2ifheadNULLpri
tf