C/C++ 中二叉排序树 的操作

#include<stdio.h>#include<iostream>using namespace std;typedef struct Node{int data;struct Node *lchild;struct Node *rchild;}Node,*pNode;void create(pNode &tree,int data){pNode ptr;if(data == -1){return;}if(tree == NULL){tree = (pNode)malloc(sizeof(Node));if(tree!=NULL){tree->data = data;tree->lchild = NULL;tree->rchild = NULL;}return ;}if(tree->data>=data){if(tree->lchild == NULL){ptr = (pNode)malloc(sizeof(Node));if(ptr!=NULL){ptr->data = data;ptr->lchild = NULL;ptr->rchild = NULL;}tree->lchild = ptr;}else{create(tree->lchild,data);}}if(tree->data<data){  if(tree->rchild == NULL){ptr = (pNode)malloc(sizeof(Node));if(ptr!=NULL){ptr->data = data;ptr->lchild = NULL;ptr->rchild = NULL;}tree->rchild = ptr;}else{create(tree->rchild,data);}}}void inorderTravel(pNode tree){if(tree){    inorderTravel(tree->lchild);printf("%d ",tree->data);inorderTravel(tree->rchild);}}void preTravel(pNode tree){if(tree){printf("%d ",tree->data);preTravel(tree->lchild);preTravel(tree->rchild);}}void postTravel(pNode tree){if(tree){postTravel(tree->lchild);postTravel(tree->rchild);printf("%d ",tree->data);}}void DeleteNode(pNode &tree){pNode ptr;ptr = tree;//如果右子树为空，左子树为空if(ptr->rchild == NULL &&ptr->lchild==NULL){free(ptr);tree = NULL;}else if(ptr->rchild == NULL&&ptr->lchild!=NULL){//找到前继节点ptr->data = ptr->lchild->data;DeleteNode(ptr->lchild);}else if(ptr->rchild != NULL&&ptr->lchild==NULL){ptr->data = ptr->rchild->data;DeleteNode(ptr->rchild);}else {ptr->data = ptr->lchild->data;DeleteNode(ptr->lchild);}}void deleteData(pNode &tree,int data){if(!tree){return ;}if(data == tree->data){return DeleteNode(tree);}else if(data < tree->data){return deleteData(tree->lchild,data);}else {return deleteData(tree->rchild,data);}}int main(void){pNode ptree = NULL;pNode ptr = NULL;int data = -2;int i=0;cin>>data;while(data!=-1){create(ptree,data);cin>>data;}preTravel(ptree);cout<<endl;inorderTravel(ptree);cout<<endl;postTravel(ptree);cout<<endl;data = -2;while(1){    cin>>data;if(data==-1){break;}deleteData(ptree,data);inorderTravel(ptree);cout<<endl;}getchar();}