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Optimal binary search tree

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Optimal binary search tree

Meera only reaches for Optimal binary search tree (alt) when folder on disk has to stay correct in a file explorer.

Do Optimal binary search tree (alt) once by hand. left < root < right. Change one input. Say the new result out loud.

Without Optimal binary search tree (alt), a file explorer gets messy and folder on disk is hard to trust.

Optimal binary search tree (alt) shows up in a file explorer. Name folder on disk, not “a real-world scenario”.

If folder on disk breaks under Optimal binary search tree (alt), check unbalanced BST becoming a list first.

Optimal binary search tree (alt) is not a lonely heading. Meera ties it to folder on disk.

Viva for Optimal binary search tree (alt): what it is → left < root < right → the mistake (unbalanced BST becoming a list).

Diagram

Exam tip

Say Optimal binary search tree (alt) in one breath, then left < root < right, then 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))

Optimal binary search tree (alt) — binary search halves a sorted array each step — O(log n).

Short notes

DefOptimal binary search tree (alt) — Meera uses it for folder on disk in a file explorer.
RuleOptimal binary search tree (alt) → left < root < right.
RememberOptimal binary search tree (alt) + Big-O (a file explorer).
UseOptimal binary search tree (alt) in a file explorer (folder on disk).
TrapOptimal binary search tree (alt) — unbalanced BST becoming a list.
ExOptimal binary search tree (alt) → 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))

Optimal binary search tree

Example

Short notes

Questions

Optimal binary search tree

Example

Short notes

Questions