数据结构大题

{?if(BT->lchild==NULL&&BT->rchild==NULL) return0;?if(BT->lchild&&BT->rchild) return1+count2(BT->lchild)+count2(BT->rchild);?if(BT->lchild&&BT->rchild==NULL) returncount2(BT->lchild);?if(BT->lchild==NULL&&BT->rchild) returncount2(BT->rchild);}intleafnum(BTREEBT)//返回叶节点个数{?staticintcount=0;?if(BT->lchild==NULL&&BT->rchild==NULL)?{ return++count;?}?else?{ leafnum(Lchild(BT)); leafnum(Rchild(BT));?}}voidCreateBTREE(BTREE&BT,char*str)//先根输入树{?charch;?ch=*str++;?if(ch=='#') BT=NULL;?else?{ BT=newnode; BT->data=ch;?CreateBTREE(BT->lchild,str);?CreateBTREE(BT->rchild,str);?}}intmain(){?BTREEBT=NULL;?char*str="abc##d##ef##g##";?CreateBTREE(BT,str);?PreOrder(BT);?cout<<endl;?InOrder(BT);?cout<<endl;?PostOrder(BT);?cout<<endl;?cout<<"度为2的节点的个数:"<<count2(BT)<<endl;?cout<<"叶子节点个数:"<<leafnum(BT)<<endl;}