234 Trees
This lesson is a brief introduction to 234 Trees. We will discuss their key features and take a look at some examples.
We'll cover the following
Introduction
234 is a search tree which is an advanced version of 23 Trees. This tree can accommodate more keys and hence more child nodes as compared to 23 Trees. Likewise, a 234 Tree satisfies all the properties covered in 23 Trees as well as some additional key features:

Each internal node can contain a max. of three keys

Each internal node can have a max. of four child nodes

In the case of three keys (left, mid, and right) at an internal node, all the keys present at the LeftChild node are smaller than the left key. This can be mathematically expressed as,
$LeftChild.keys < LeftKey$
 All the keys present at the LeftMidChild node are smaller than the mid key, which can be mathematically expressed as,
$LeftMidChild.keys < MidKey$
 All the keys present at the RightMidChild node are smaller than the right key, which can be mathematically expressed as,
$RightMidChild.keys < RightKey$
 Finally, all the keys present at the RightChild node are greater than the right key, which can be mathematically expressed as,
$RightChild.keys > RightKey$
Example
Given below is an example of 234 Trees. The insertion/deletion is performed in the same way as we did in 23 Trees, keeping in mind the fact that nodes in 234 Trees are allowed to have three keys at a time instead of two.
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