;集群内向n台服务器广播dMB数据;int LEAF2(BTREE T) { if(T==NULL) return 0; if(T->lchild==NULL & T->rchild==NULL) return 1; return LEAF2(T->child)+LEAF2(T->rchild; };A( B( D , C( F( , E , G) ) ;从左至右依次从广义表中取元素#define