bst_insertio.cpp

#include <iostream>
#include <stdio.h>

using namespace std;

struct node {
    int key;
    node *parent;
    node *left;
    node *right;
};

class btree {
public:
    btree();
    void insert(int, node*);
    void inordertraverse(node*);

private:
    node *root;
};

btree::btree(){}

void btree::insert(int key, node *x) {
    printf("Insert %d\n",key);
    node *z = new node();
    z->key = key;
    node *y = new node();

    while(x!=NULL) {
        y = x;
        if(z->key < x->key) {
            x = x->left;
        }
        else {
            x = x->right;
        }
    }
    z->parent = y;
    if(!y) {
        this->root = z;
    }
    else if(z->key < y->key) {
        y->left = z;
    }
    else {
        y->right = z;
    }
}

void btree::inordertraverse(node* tree) {
    if(tree) {
        inordertraverse(tree->left);
        cout<<tree->key<<" "<<endl;
        inordertraverse(tree->right);
    }
}

int main() {
    btree bst;
    node root = node();
    
    root.key=3;
    bst.insert(2, &root);
    bst.insert(4, &root);
    bst.insert(1, &root);
    bst.insert(6, &root);
    bst.insert(7, &root);

    bst.inordertraverse(&root);
return 0;
}