Binary trees are a fundamental data structure in computer science. They provide a way to organize and structure hierarchical data. Level order traversal is a popular traversal algorithm that visits each node at each level of the tree from left to right.

In this blog post, we will explore how to perform level order traversal on a binary tree using a queue in C++. This approach ensures that we visit all nodes at each level before moving on to the next level. Let’s get started!

Understanding Level Order Traversal

Level order traversal visits the nodes of a binary tree in a breadth-first manner. It starts at the root node and visits all nodes at the same level before moving on to the next level. This traversal algorithm is implemented using a queue data structure.

Implementing Level Order Traversal in C++

To perform level order traversal on a binary tree, we need to use a queue data structure. Here’s a C++ code snippet that demonstrates the implementation:

#include <iostream>
#include <queue>

// Structure for a binary tree node
struct Node {
    int data;
    Node* left;
    Node* right;
};

// Function to perform level order traversal
void levelOrderTraversal(Node* root) {
    // Base case: If the tree is empty
    if (root == nullptr) {
        return;
    }
    
    // Create an empty queue for level order traversal
    std::queue<Node*> queue;
    
    // Enqueue the root node
    queue.push(root);
    
    while (!queue.empty()) {
        // Dequeue the front node and print its data
        Node* current = queue.front();
        std::cout << current->data << " ";
        
        // Enqueue the left child if it exists
        if (current->left != nullptr) {
            queue.push(current->left);
        }
        
        // Enqueue the right child if it exists
        if (current->right != nullptr) {
            queue.push(current->right);
        }
        
        // Dequeue the processed node
        queue.pop();
    }
}

// Driver code
int main() {
    // Create a binary tree
    Node* root = new Node();
    root->data = 1;
    root->left = new Node();
    root->left->data = 2;
    root->right = new Node();
    root->right->data = 3;
    root->left->left = new Node();
    root->left->left->data = 4;
    root->left->right = new Node();
    root->left->right->data = 5;
    
    // Perform level order traversal on the binary tree
    levelOrderTraversal(root);
    
    return 0;
}

Conclusion

Level order traversal is a useful algorithm to visit each node in a binary tree in breadth-first fashion. By using a queue to keep track of the nodes at each level, we can efficiently perform the traversal. The C++ implementation provided in this blog post demonstrates the basic implementation of level order traversal using a queue.

By understanding and implementing this algorithm, you’ll have a strong foundation for working with binary trees and performing various operations on them.

Happy coding!

#C++ #BinaryTreeTraversal