智能指针的二叉搜索树

Question

I used row pointers to implement the binary search tree data structure and it worked perfectly, but when I replaced the row pointers with shared_ptr it compiles successfully but the program crashes due to unknown run-time error. Could you please help in this?

#include<iostream>
#include<memory>
class node{
public:
int data;
std::shared_ptr<node>left = std::make_shared<node>();
std::shared_ptr<node>right = std::make_shared<node>();
};

std::shared_ptr<node>CreateNode(int x);
void print_tree(const std::shared_ptr<node>&x);

int main(){
    auto root = std::make_shared<node>();
    root = CreateNode(12);
    root->left = CreateNode(9);
    root->right = CreateNode(14);
    root->left->right = CreateNode(10);
    root->left->right = CreateNode(11);
    print_tree(root);
    return 0;
}

std::shared_ptr<node>CreateNode(int x){
    std::shared_ptr<node>NewNode = std::make_shared<node>();
    NewNode->data = x;
    NewNode->left = NewNode->right = nullptr;
    return NewNode;
}

void print_tree(const std::shared_ptr<node>&x){ 
    if(x==nullptr) return;
    std::cout<<x->data<<std::endl;
    print_tree(x->left);
    print_tree(x->right);
}

Answer 1

#include<iostream>
#include<memory>

class node
{
public:
    int data;
    std::shared_ptr<node>left;
    std::shared_ptr<node>right;
};

std::shared_ptr<node>CreateNode(int x);
void print_tree(const std::shared_ptr<node>&x);

int main()
{
    auto root = CreateNode(12);
    root->left = CreateNode(9);
    root->right = CreateNode(14);
    root->left->right = CreateNode(10);
    root->left->right = CreateNode(11);
    print_tree(root);
    return 0;
}

std::shared_ptr<node>CreateNode(int x)
{
    std::shared_ptr<node>NewNode = std::make_shared<node>();
    NewNode->data = x;
    NewNode->left = NewNode->right = nullptr;
    return NewNode;
}

void print_tree(const std::shared_ptr<node>&x)
{
    if(x==nullptr) return;
    std::cout<<x->data<<std::endl;
    print_tree(x->left);
    print_tree(x->right);
}

This works on my machine. I made left and right pointers in node class initially equal to nullptr , instead of creating new node because you can't know is it going to be used. And root to be initialized by result of CreateNode function.