单项选择题
A.s->link=p;p->link=s; B.s->link=p->link:p->link=s: C.S->link=p->link; p=s: D.p->link=s:s->link=p:
A.vulnerable B.week C.sensitively D.helpless
A.p={HK,HI,IJ,JKL,HL} B.P={HIL,IKL,IJL} C.P={HJ,IK,HL} D.P={HI,JK,HL}