# Preorder Traversal

A preorder traversal is a type of tree traversal that visits the root node first, followed by the left subtree, and then the right subtree. It is called a preorder traversal because the root node is always visited before any of its child nodes.

## What is Preorder Traversal?

Preorder traversal is a type of tree traversal that visits the root node first, followed by the left subtree, and then the right subtree. This is in contrast to postorder traversal, which visits the left subtree first, followed by the right subtree, and then the root node. Preorder traversal is also sometimes called depth-first search.

## Applications of Preorder Traversal

Preorder traversal is a popular technique for traversing trees and graphs. Many applications make use of preorder traversal, including:

â€¢ Generating a list of files in a directory tree

â€¢ Parsing XML documents

â€¢ Constructing syntax trees for compilers

â€¢ Calculating mathematical expressions are given in prefix notation

â€¢ Converting infix notation to prefix notation

## Working of Preorder Traversal

The preorder traversal is one of the most commonly used tree traversal algorithms. As the name suggests, preorder traversal visits each node in a tree before its child nodes. This method is often used when we need to process or print the nodes of a tree in a specific order.

The steps for preorder traversal are as follows:

1. Visit the root node.

2. Traverse the left subtree in preorder.

3. Traverse the right subtree in preorder.

As you can see, preorder traversal visits each node in a tree before its child nodes. This makes it different from postorder and inorder traversals, which visit the child nodes before the root node. Preorder traversal is often used when we need to process or print the nodes of a tree in a specific order.

There are many reasons why you might want to use preorder traversal on your blog. Here are just a few advantages:

1. You can control the order in which your posts are displayed.

2. You can highlight certain posts that you want your readers to see first.