二叉搜索树的Insert、Find、FindMin、FindMax、Delete、MakeEmpty

searchTree.h 功能实现

/*==============================================二叉查找树（BSTree）的Insert、Find、FindMin、FindMax、Delete、MakeEmpty编译环境：Visual Studio 2012Date: 2015/01/17==============================================*/#include <stdlib.h>#include <string>#include <iostream>using namespace std;typedef int elemType;typedef struct node BSTreeNode;typedef struct node BSTree;struct node{elemType elem;BSTreeNode* left;BSTreeNode* right;};void fatalError(const std::string str){cout << "ERROR: "<< str <<endl;system("pause");exit(-1);}BSTreeNode* makeBSTreeEmpty(BSTree* bstree){if (bstree != NULL){makeBSTreeEmpty(bstree->left);makeBSTreeEmpty(bstree->right);free(bstree);}return bstree;}BSTreeNode* insertBStree(BSTree* bstree, elemType x){if (bstree == NULL){bstree = (BSTree *)malloc(sizeof(*bstree));if(bstree == NULL)fatalError("分配BSTree节点异常");bstree->elem = x;bstree->left = NULL;bstree->right = NULL;}else{if (x < bstree->elem){bstree->left = insertBStree(bstree->left, x);}else if (x > bstree->elem){bstree->right = insertBStree(bstree->right, x);}}return bstree;}BSTreeNode* findElem(BSTree* bstree, elemType x){if(bstree == NULL){cout << "没有找到元素：" << x <<endl;return NULL;}else if (x < bstree->elem){ findElem(bstree->left, x);}else if(x > bstree->elem){ findElem(bstree->right, x);}else{return bstree;}}BSTreeNode* findMinElem(BSTree* bstree){if (bstree == NULL){fatalError("findMinElem：树为空");}else if (bstree->left == NULL){return bstree;}else{findMinElem(bstree->left);}}BSTreeNode* findMaxElem(BSTree* bstree) //递归实现{if (bstree == NULL){fatalError("findMaxElem：树为空");}else if (bstree->right == NULL){return bstree;}else{findMaxElem(bstree->right);}}BSTreeNode* findMaxElem2(BSTree* bstree) //非递归实现{if (bstree == NULL){fatalError("findMaxElem：树为空");}while(bstree->right != NULL){bstree = bstree->right;}return bstree;}BSTreeNode *deleteElem(BSTree* bstree, elemType x){BSTreeNode* tempNode = NULL;//删除节点不能通过findElem()函数查找x 元素地址后实现，因为无法获得x 前一结点的地址（可另写一个函数findPrevElem()实现）if (bstree == NULL){cout << "该BSTree 不含有元素: " << x <<endl;}else if (x < bstree->elem) // x在左子树中，向左递归{bstree->left = deleteElem(bstree->left, x);}else if (x > bstree->elem){bstree->right = deleteElem(bstree->right, x);}else //找到元素x的位置：x == bstree->elem,进行删除{//===  1或0个child  ======tempNode = bstree;if (bstree->left == NULL){bstree = bstree->right;}else if (bstree->right == NULL){bstree = bstree->left;free(tempNode);}//===  2个child  ======else{tempNode = findMinElem(bstree->right); //选右子树的最小值代替被删除节点的元素值（或者：选左子树中的最大值）bstree->elem = tempNode->elem;bstree->right = deleteElem(bstree->right, tempNode->elem); //删除右子树中的最小值（min没有左子树）}//free(tempNode);//free()如果在此处会导致free两次}return bstree;}

searchTree.cpp 测试函数

#include "searchTree.h"int main(){BSTree* T = NULL;elemType a[] = {30,50,20,40,25,70,54,23,80,92};for (int i = 0; i < sizeof(a)/sizeof(a[0]); i++){ T = insertBStree(T, a[i]);}findElem(T, 10);for (int i = 0; i < sizeof(a)/sizeof(a[0]); i++){cout << a[i] << "  0x" << findElem(T, a[i]) << endl; }cout << endl;cout << "Min: addr--0x" << findMinElem(T) <<endl;cout << "1-Max: addr--0x" << findMaxElem(T) <<endl;cout << "2-Max: addr--0x" << findMaxElem2(T) <<endl;deleteElem(T, 10);deleteElem(T, 50);for (int i = 0; i < sizeof(a)/sizeof(a[0]); i++){cout << a[i] << "  0x" << findElem(T, a[i]) << endl; }cout << endl;makeBSTreeEmpty(T);system("pause");return 0;}

参考资料：《数据结构与算法分析——C语言描述》  P73