Binary Search Tree
Domain: Data Structures
🎯 Motivation
A BST keeps data sorted so you can search, insert, and delete efficiently: left child is smaller, right child is larger.
📋 Concrete Example
Searching for 25 in a BST with root 50: 25 < 50, go left; 25 > 20, go right; found 25. Each step eliminates half the tree.
🔗 Analogy
A phone book organised by surname. If you are looking for Chan, you open to the middle, see Lee, know C comes before L, and flip to the left half.