Lecture 299:- Creating a Binary Search Tree

Here's a C++ code to create a Binary Search Tree (BST) by taking user input for node values and inserting them one by one into the BST:

cppCopy code

#include <iostream> using namespace std; struct TreeNode {    int val;    TreeNode* left;    TreeNode* right;    TreeNode(int data) : val(data), left(nullptr), right(nullptr) {} }; // Recursive function to insert a new node in a BST TreeNode* insertBST(TreeNode* root, int val) {    if (root == nullptr)        return new TreeNode(val);    if (val < root->val)        root->left = insertBST(root->left, val);    else if (val > root->val)        root->right = insertBST(root->right, val);    return root; } void inOrderTraversal(TreeNode* root) {    if (root == nullptr)        return;    inOrderTraversal(root->left);    cout << root->val << " ";    inOrderTraversal(root->right); } int main() {    // Create an empty binary search tree    TreeNode* root = nullptr;    int n, val;    cout << "Enter the number of nodes: ";    cin >> n;    cout << "Enter " << n << " values to insert into the BST:" << endl;    for (int i = 0; i < n; i++) {        cin >> val;        root = insertBST(root, val);    }    // Perform an in-order traversal to see the sorted BST    cout << "In-order Traversal of BST: ";    inOrderTraversal(root);    cout << endl;    // Remember to free the allocated memory after use to avoid memory leaks.    // You can implement a function to delete the entire tree if needed.    return 0; }

Sample Input:

sqlCopy code

Enter the number of nodes: 7 Enter 7 values to insert into the BST: 5 3 8 2 4 7 9

Output:

cssCopy code

In-order Traversal of BST: 2 3 4 5 7 8 9

In this code, the user is prompted to enter the number of nodes and then enter the values of each node one by one. The BST is constructed by inserting the values in the correct order. The in-order traversal is performed to display the BST in sorted order.