这是我的二叉搜索树代码。我在使用deleteNode函数时遇到错误。而不是删除它设置节点等于零。
#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <iomanip>
using namespace std;
struct Node {
int data;
Node *left, *right;
Node() {left = right = NULL;}
};
class Bst {
public:
int count;
int space;
Node *root;
Bst() {
root = NULL;
count = 0;
space = 0;
}
void insertNode(int data) {
Node *newNode = new Node;
newNode->data = data;
insert_r(root, newNode);
}
void insert_r(Node *&root, Node *newNode) {
if (root == NULL) {
root = newNode;
return;
}
if (newNode->data < root->data) {
insert_r(root->left, newNode);
}
else if (newNode->data > root->data) {
insert_r(root->right, newNode);
}
else{
Node *newNode = NULL;
delete newNode;
}
}
void display_bst() {
display_tree_r(root, space);
}
void display_tree_r(Node *root, int space) {
if(root != NULL) {
if(root->right) {
display_tree_r(root->right, space + 4);
}
if (space) {
cout << setw(space) << ' ';
}
if (root->right) cout << " /\n" << setw(space) << ' ';
cout << root->data << "\n ";
if(root->left) {
cout << setw(space) << ' ' << " \\\n";
display_tree_r(root->left, space + 4);
}
}
}
void remove(int num) {
deleteNode(num, root);
}
void deleteNode(int num, Node *root) {
if (num < root->data)
deleteNode(num, root->left);
else if (num > root->data)
deleteNode(num, root->right);
else
makeDeletion(root);
}
void makeDeletion(Node *&nodePtr) {
Node *tempNodePtr = NULL;
if (nodePtr == NULL)
cout << "Cannot delete empty node.\n";
else if (nodePtr->right == NULL) {
tempNodePtr = nodePtr;
nodePtr = nodePtr->left; // Reattach the left child.
delete tempNodePtr;
}
else if (nodePtr->left == NULL) {
tempNodePtr = nodePtr;
nodePtr = nodePtr->right; // Reattach the right child.
delete tempNodePtr;
}
else {
tempNodePtr = nodePtr->right;
while (tempNodePtr->left)
tempNodePtr = tempNodePtr->left;
tempNodePtr->left = nodePtr->left;
tempNodePtr = nodePtr;
nodePtr = nodePtr->right;
delete tempNodePtr;
}
}
};
int main() {
Bst bst;
bst.insertNode(5);
bst.insertNode(8);
bst.insertNode(7);
bst.insertNode(9);
bst.insertNode(2);
bst.insertNode(3);
bst.insertNode(1);
bst.display_bst();
cout << endl << endl << endl;
cout << endl << endl << endl;
bst.remove(5);
bst.display_bst();
return 0;
}
这是我得到的输出我希望树自我修复，下一个节点出现但我得到了第二棵树。我的问题是如何解决它，为什么它将5设置为零。
9
/
8
\
7
/
5
\
3
/
2
\
1
9
/
8
\
7
\
3
/
2
\
1
/
0
\
3
/
2
\
1