Get Sum of elements Level wise in a Binary Tree

Question:

Given a binary tree root node, get the level wise sum.

Example:

Consider the image given below

Level 1 Sum = 16
Level 2 Sum = 10 + 25 = 35
Level 3 Sum = 7 + 15 + 18 + 30 = 70

Solution:

While doing level order traversal, compute the sum at each level and print it to output.

Solution on C++

#include <iostream>
#include <queue>
#include <stack>
using namespace std;

// structure to hold binary tree node
struct Node
{
    int data;
    Node *left, *right;

    Node(int data)
    {
        this->data = data;
        this->left = this->right = nullptr;
    }
};

int get_level_sum( Node *root) 
{ 
    if (root == NULL) 
        return 0;   

    queue<Node*> q; 
    q.push(root); 
    
    while (!q.empty()) 
    { 

        int count = q.size() ; 
  
        int level_sum = 0; 
        while (count--) 
        { 
            Node *temp = q.front(); 
            q.pop(); 
  
            level_sum = level_sum + temp->data; 
  
            if (temp->left != NULL) 
                q.push(temp->left); 
            if (temp->right != NULL) 
                q.push(temp->right); 
        } 
  
        cout<<"Level sum = "<<level_sum<<endl;
    } 
  
    return 0; 
} 

int main()  
{  
    Node* root = nullptr;
    /* Binary tree:
              16
            /   \
           /     \
          10      25
         /  \    /  \
        /    \  /    \
       7    15 18     30

    */

    root = new Node(16);
    root->left = new Node(10);
    root->right = new Node(25);
    root->left->left = new Node(7);
    root->left->right = new Node(15);
    root->right->left = new Node(18);
    root->right->right = new Node(30);

    get_level_sum(root);

    return 0;  
}  

Output:

Level sum = 16
Level sum = 35
Level sum = 70