二叉搜索树的一些操作的C++实现

#include<iostream>
using namespace std;
typedef struct BiTNode
{
    int data;
    int key;
    struct BiTNode *parent, *lchild, *rchild;
}BiTNode, *BiTree;
BiTree Tree_Search(BiTree x, int k);
void Tree_Walk(BiTree x);
BiTree Tree_Minimun(BiTree x);
BiTree Tree_Maximun(BiTree x);
void Tree_Insert(BiTree &T, BiTree z);
void Tree_Delete(BiTree &T, BiTree z);
void Transplant(BiTree &T, BiTree u, BiTree v);

#include "searchTree.h"
BiTree Tree_Search(BiTree x, int k)  //查找二叉搜索树。Tree-Search返回一个指向关键字为key的节点的指针；否则返回NULL
{
    if ((x == NULL) || (k == x->key))
    {
        return x;
    }
    if (k < x->key)
    {
        return Tree_Search(x->lchild, k);
    }
    else
    {
        return Tree_Search(x->rchild, k);
    }
}
void Tree_Walk(BiTree x)  //遍历
{
    if (x != NULL)
    {
        Tree_Walk(x->lchild);
        cout << x->key << endl;
        Tree_Walk(x->rchild);
    }
}
BiTree Tree_Minimun(BiTree x)
{
    while (x->lchild != NULL)
    {
        x = x->lchild;
    }
    return x;
}
BiTree Tree_Maximun(BiTree x)
{
    while (x->rchild != NULL)
    {
        x = x->rchild;
    }
    return x;
}
void Tree_Insert(BiTree &T,BiTree z)
{
    BiTree y = NULL;
    BiTree x = T;    
    while (x != NULL)
    {
        y = x;
        if (z->key < x->key)
        {
            x = x->lchild;
        }
        else
        {
            x = x->rchild;
        }
    }
    z->parent = y;
    if (y == NULL)
    {
        T = z;  
    }
    else if (z->key < y->key)
    {
        y->lchild = z;
    }
    else
    {
        y->rchild = z;
    }
}
void Transplant(BiTree &T, BiTree u, BiTree v)
{
    if (u->parent == NULL)
    {
        T = v;
    }
    else if (u == u->parent->lchild)
    {
        u->parent->lchild = v;
    }
    else
    {
        u->parent->rchild = v;
    }
    if (v != NULL)
    {
        v->parent = u->parent;
    }
}
void Tree_Delete(BiTree &T, BiTree z)
{
    if (z->lchild == NULL)
    {
        Transplant(T, z, z->rchild);
    }
    else if (z->rchild == NULL)
    {
        Transplant(T, z, z->lchild);
    }
    else
    {
        BiTree y = Tree_Minimun(z->rchild);
        if (y->parent != z)
        {
            Transplant(T, y, y->rchild);
            y->rchild = z->rchild;
            y->rchild->parent = y;
        }
        Transplant(T, z, y);
        y->lchild = z->lchild;
        y->lchild->parent = y;
    }
}
int main()
{
    BiTree oldTree = NULL;
    for (int i = 0; i < 10; ++i)
    {
        BiTree testNode = new BiTNode();
        testNode->key = rand()%100;
        Tree_Insert(oldTree, testNode);
    }
    Tree_Walk(oldTree);
    cout << "The Max is   " << Tree_Maximun(oldTree)->key << endl;
    cout << "The Max is   " << Tree_Minimun(oldTree)->key << endl;
    Tree_Delete(oldTree, Tree_Maximun(oldTree));
    Tree_Delete(oldTree, Tree_Minimun(oldTree));
    Tree_Walk(oldTree);
    return 0;
}