Tricky pointer basics explained | Recursive implementation of insertion into binary search tree

insert_recursive.cpp

tree_node* insert(tree_node* n, int value)
{
    if (n == NULL)
    {
        tree_node* new_node = new tree_node();
        new_node->data = value;
        new_node->left = new_node->right = NULL;
        return new_node;
    }

    if (value == n->data)
    {
        return n;
    }

    if (value < n->data)
    {
        n->left = insert(n->left, value);
    }
    else
    {
        n->right = insert(n->right, value);
    }
    
    return n;
}