Feature #3: Traversing DOM Tree II
Explore an improved technique for traversing DOM trees efficiently by adding next pointers to connect nodes at the same level. This lesson helps you understand how to process large web page trees without extra space, enabling optimized traversal and manipulation of n-ary tree structures in web scraping and related tasks.
We'll cover the following...
Description
The technique we used previously to traverse through the web tree used too much space. The number of web pages can be enormous, and traversing all of them will consume a lot of unnecessary space. Therefore, we have come up with a better approach in which we create a shadow tree for the DOM where each node has a pointer to the next node to its right on the same level.
We’ll introduce an additional attribute, next, to our TreeNode structure. The next node will point to its immediate right node on the same level. If there is no right node to point, next will point to null. This next pointer will allow us to avoid the queue data structure that we used previously to traverse the tree, resulting in a space-efficient approach.
We’ll be provided with a root node of an n-ary tree. The root node in our case will again be the body tag. This root node will have the complete web page nested within its children. We have to go through each node and assign the next pointer to the node to its immediate right on the same level.
Let’s try to understand this better with an illustration:
Solution
The tree structure that we get from the web is arbitrary, meaning a parent node can have any number of child nodes and the ...