nodes at k cpp

// program to print child nodes at distance k from the given node

#include <iostream>
#include <queue>
#include <map>

using namespace std;

// node class
class node{
public:
    int data;
    node* left;
    node* right;
};

// function that returns a pointer to new node
node* createNode(int element){
    node* temp = (node*) malloc(sizeof(node));
    temp->data = element;
    temp->left = NULL;
    temp->right = NULL;
    return temp;
}


// function to print child nodes at a distance k from the given node
void print_nodes_at_K(node* root, int K){
    if(root == NULL || K < 0){
        return;
    }
    if(K == 0){
        cout<<root->data<<" ";
    }
    if(K > -1) {
        print_nodes_at_K(root->left, K - 1);
        print_nodes_at_K(root->right, K - 1);
    }
}


int main() {
    node* head = createNode(1);
    head->left = createNode(2);
    head->right = createNode(3);
    head->left->left = createNode(4);
    head->left->right = createNode(5);
    head->right->right = createNode(6);
    head->left->left->right = createNode(7);
    head->right->right->left = createNode(8);
    head->left->left->right->left = createNode(9);
    head->left->left->right->left->left = createNode(10);
    head->right->right->left->right = createNode(11);
    head->hd = 0;

    cout<<"Nodes at distance 2 from the root node are : ";
    print_nodes_at_K(head, 2);
}

/*

Nodes at distance 2 from the root node are : 4 5 6
Process finished with exit code 0

*/