# What Is BST Tree in Data Structure?

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Larry Thompson

A Binary Search Tree (BST) is a commonly used data structure in computer science. It is a type of binary tree that has a specific ordering property, making it efficient for searching, insertion, and deletion operations.

## Understanding Binary Search Trees

A binary tree is a hierarchical data structure consisting of nodes, where each node has at most two children referred to as the left child and the right child. In a BST, the left child of a node contains a value smaller than the node’s value, while the right child contains a value larger than the node’s value.

This ordering property makes searching for elements in a BST efficient. When searching for an element, we start at the root node and compare the Target value with the current node’s value. Based on this comparison, we move to either the left or right child until we find the desired element or reach a null reference indicating that it does not exist in the tree.

## Benefits of Using BSTs

Binary Search Trees offer several advantages:

• Efficient Searching: The ordering property allows for efficient searching operations with an average time complexity of O(log n) for balanced trees. This makes BSTs suitable for applications that require fast retrieval of data.
• Ordered Data: The elements in a BST are stored in sorted order, which can be useful when you need to traverse them in ascending or descending order.
• Dynamic Size: Unlike arrays or static-sized data structures, BSTs can dynamically grow and shrink as elements are added or removed.

## Operations on Binary Search Trees

In addition to searching, BSTs support other fundamental operations:

### Insertion

To insert a new element into a BST, we begin by comparing the value with the root node. If it is less than the root value, we move to the left child; if it is greater, we move to the right child.

We repeat this process recursively until we find a null reference. Once found, we create a new node with the given value and link it accordingly.

### Deletion

Deleting an element from a BST can be more complex compared to insertion. There are three cases to consider:

1. If the node to be deleted has no children, we simply remove it from the tree.
2. If the node has only one child (left or right), we replace it with its child.
3. If the node has two children, we find either its predecessor (the largest value in its left subtree) or its successor (the smallest value in its right subtree). We then replace the node’s value with that of its predecessor or successor and recursively delete that predecessor or successor.

## Conclusion

A Binary Search Tree is an essential data structure for efficient searching and maintaining ordered data. Its properties make it suitable for various applications where fast retrieval operations are required. By understanding how BSTs work and mastering their operations, you can leverage their power to solve complex problems effectively.