Question

在C ++中实现BST时遇到问题。当我向BST插入大约20,000个数据的小数据时，它运行良好。如果我尝试在100,000左右插入大量数据。 BST收到运行时错误。你能帮助我吗？

这是我的实施。 Binary Search.h

#include <iostream>
#include <stdlib.h>
#include <conio.h>

using namespace std;

struct treeNode
{
    long long data;
    treeNode *left;
    treeNode *right;
};

treeNode *insertNode(treeNode *node,long long data)
{
    if(node==NULL)
    {

        treeNode *temp = new treeNode;
        //temp = (treeNode *)malloc(sizeof(treeNode));
        temp -> data = data;
        temp -> left = temp -> right = NULL;
        return temp;
    }
    if(data >(node->data))
    {
        node->right = insertNode(node->right,data);
    }
    else if(data < (node->data))
    {
        node->left = insertNode(node->left,data);
    }
    /* Else there is nothing to do as the data is already in the tree. */
    return node;
}

treeNode * searchNode(treeNode *node, long long data)
{
    if(node==NULL)
    {
        /* Element is not found */
        return NULL;
    }
    if(data > node->data)
    {
        /* Search in the right sub tree. */
        return searchNode(node->right,data);
    }
    else if(data < node->data)
    {
        /* Search in the left sub tree. */
        return searchNode(node->left,data);
    }
    else
    {
        /* Element Found */
        return node;
    }
}
void displayInorder(treeNode *node)
{
    if(node==NULL)
    {
        return;
    }
    displayInorder(node->left);
    cout<<" " << node->data<<" ";
    displayInorder(node->right);
}
void displayPreorder(treeNode *node)
{
    if(node==NULL)
    {
        return;
    }
    cout<<" " <<node->data<<" ";
    displayPreorder(node->left);
    displayPreorder(node->right);
}
void displayPostorder(treeNode *node)
{
    if(node==NULL)
    {
        return;
    }
    displayPostorder(node->left);
    displayPostorder(node->right);
    cout<<" " <<node->data<<" ";
}

我在以下位置收到运行时错误：

node->right = insertNode(node->right,data);

请帮帮我们。

提前谢谢！

Answer 1

您可能会在所有递归中耗尽堆栈，因此您可以增加堆栈，或者编写一些（或全部）函数以使用迭代而不是递归（尽管预订，后序，顺序遍历）难以正确地写为循环）。

以下是Search和Insert方法的简单示例：

struct TreeNode
{
    long long data = 0;
    std::shared_ptr<TreeNode> left;
    std::shared_ptr<TreeNode> right;
    TreeNode(long long _data) : data(_data){}
};

class BST
{
    public:
    void Insert(std::shared_ptr<TreeNode> node)
    {
        if (!node)
           throw std::runtime_error("Cannot insert null node");

        if (!root)
        {
           root = node;
           return;
        }

        std::shared_ptr<TreeNode>* next = &root;
        while(*next)
        {
            if (node->data < (*next)->data)
                next = &((*next)->left);
            else
                next = &((*next)->right);
        }
        *next = node;
    }

    std::pair<bool, std::shared_ptr<TreeNode>> Search(long long data)
    {
        if (!root)
           return std::make_pair(false, nullptr); // searching empty tree

        std::shared_ptr<TreeNode> next = root;
        while(next)
        {
            if (data < next->data)
                next = next->left;
            else if (data > next->data)
                next = next->right;
            else
                return std::make_pair(true, next); // match found
        }

        // no match found
        return std::make_pair(false, nullptr);
    }

    private:
    std::shared_ptr<TreeNode> root;
};

可以找到完整的工作演示here

二进制搜索树实现C ++运行时错误

1 个答案: