## Introduction

Binary tree traversal is a fundamental concept in computer science and data structures. It involves visiting all nodes in a binary tree, in a specific order. One such order is breadth-first traversal, which visits nodes in level-order, from left to right. In this article, we will explore binary tree breadth-first traversal in relaxed English language.

## What is a Binary Tree?

A binary tree is a tree data structure in which each node has at most two children, referred to as the left child and the right child. The topmost node in a binary tree is called the root node. The nodes that do not have any children are called leaf nodes.

## What is Breadth-First Traversal?

Breadth-first traversal, also known as level-order traversal, visits all the nodes in a binary tree level by level, starting from the root node. In other words, it visits all the nodes at a given level before moving on to the next level. The traversal proceeds from left to right at each level.

## How Does Breadth-First Traversal Work?

Breadth-first traversal uses a queue data structure to keep track of the nodes to be visited. Initially, the root node is inserted into the queue. Then, while the queue is not empty, the first node in the queue is removed and visited. If the removed node has any children, they are inserted into the queue. This process continues until all the nodes have been visited.

## Pseudo Code for Breadth-First Traversal

1. Create a queue and insert the root node into it. 2. While the queue is not empty: a. Remove the first node from the queue. b. Visit the node. c. If the node has a left child, insert it into the queue. d. If the node has a right child, insert it into the queue. 3. End while.

## Example

Let’s consider the following binary tree:

1 / \ 2 3 / \ \ 4 5 6

The breadth-first traversal of this tree would visit the nodes in the following order: 1, 2, 3, 4, 5, 6.

## Advantages of Breadth-First Traversal

Breadth-first traversal has several advantages over other traversal methods. Firstly, it ensures that nodes at a lower level are visited before nodes at a higher level. This can be useful in certain algorithms, such as finding the shortest path between two nodes. Secondly, it can be used to print the nodes in a binary tree level by level, which can be helpful in visualizing the tree.

## Conclusion

In this article, we have discussed binary tree breadth-first traversal, a method for visiting all the nodes in a binary tree in level-order. We have seen how breadth-first traversal works, and its advantages over other traversal methods. Understanding traversal algorithms is essential in computer science, and breadth-first traversal is an important concept to master.