Count all pairs of adjacent nodes whose XOR is an odd number in C++

In this tutorial, we will be discussing a program to find the number of pairs of adjacent nodes whose XOR is an odd number.

For this we will be provided with a binary tree. Our task is to count the number of pairs of adjacent elements whose XOR is an odd number.

Example

 Live Demo

#include <iostream>
using namespace std;
//node structure of tree
struct Node {
   int data;
   struct Node *left, *right;
};
//finding the pairs whose XOR
//is odd
int count_pair(Node* root, Node *parent=NULL){
   if (root == NULL)
      return 0;
   //checking pair of XOR is odd or not
   int res = 0;
   if (parent != NULL && (parent->data ^ root->data) % 2)
      res++;
   return res + count_pair(root->left, root) + count_pair(root->right, root);
}
//creation of new node
Node* newNode(int data){
   Node* temp = new Node;
   temp->data = data;
   temp->left = NULL;
   temp->right = NULL;
   return temp;
}
int main(){
   struct Node* root = NULL;
   root = newNode(15);
   root->left = newNode(13);
   root->left->left = newNode(12);
   root->left->right = newNode(14);
   root->right = newNode(18);
   root->right->left = newNode(17);
   root->right->right = newNode(21);
   printf("%d ", count_pair(root));
   return 0;
}

Output

5