DSA · Theory

Balanced Binary Search Tree

Theory

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Balanced Binary Search Tree

If you can teach Balanced Binary Search Tree using folder on disk, you know it. If you only know the heading, you don’t.

Balanced Binary Search Tree order — meaning → left < root < right → one limit. Dumping ten features helps nobody.

Skip Balanced Binary Search Tree and unbalanced BST becoming a list shows up in a file explorer.

Meera ships Balanced Binary Search Tree in a file explorer. That is the use case worth saying.

Balanced Binary Search Tree trap — unbalanced BST becoming a list. Meera loses marks for that every viva.

Balanced Binary Search Tree is not a lonely heading. Meera ties it to folder on disk.

Close Balanced Binary Search Tree with: “If I skip it, folder on disk goes wrong like this: unbalanced BST becoming a list.”

Diagram

Exam tip

Board: folder on disk. Dry-run Balanced Binary Search Tree. Name the trap: unbalanced BST becoming a list.

Example

def binary_search(arr, target):
    lo, hi = 0, len(arr) - 1
    while lo <= hi:
        mid = (lo + hi) // 2
        if arr[mid] == target:
            return mid
        if arr[mid] < target:
            lo = mid + 1
        else:
            hi = mid - 1
    return -1

print(binary_search([1, 3, 5, 7, 9], 7))

Balanced Binary Search Tree — binary search halves a sorted array each step — O(log n).

Short notes

DefBalanced Binary Search Tree — Meera uses it for folder on disk in a file explorer.
RuleBalanced Binary Search Tree → left < root < right.
RememberBalanced Binary Search Tree + time vs memory (a file explorer).
UseBalanced Binary Search Tree in a file explorer (folder on disk).
TrapBalanced Binary Search Tree — unbalanced BST becoming a list.
ExBalanced Binary Search Tree → folder on disk.

def binary_search(arr, target): lo, hi = 0, len(arr) - 1 while lo <= hi: mid = (lo + hi) // 2 if arr[mid] == target: return mid if arr[mid] < target: lo = mid + 1 else: hi = mid - 1 return -1 print(binary_search([1, 3, 5, 7, 9], 7))

Balanced Binary Search Tree

Example

Short notes

Questions

Balanced Binary Search Tree

Example

Short notes

Questions