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Binary Search Tree

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Binary Search Tree

Binary Search Tree sits in a file explorer. Riya’s job is folder on disk. Write that first.

Do Binary Search Tree once by hand. left < root < right. Change one input. Say the new result out loud.

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

Use Binary Search Tree when folder on disk must stay clear. If a simpler DSA step works, use that instead.

If folder on disk breaks under Binary Search Tree, check unbalanced BST becoming a list first.

After Binary Search Tree, Riya should still remember unbalanced BST becoming a list.

Viva for Binary Search Tree — what it is → left < root < right → the mistake (unbalanced BST becoming a list).

Diagram

Exam tip

For Binary Search Tree: definition + a file explorer + one failure.

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))

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

Short notes

DefBinary Search Tree — Riya uses it for folder on disk in a file explorer.
RuleBinary Search Tree → left < root < right.
RememberBinary Search Tree + Big-O (a file explorer).
UseBinary Search Tree in a file explorer (folder on disk).
TrapBinary Search Tree — unbalanced BST becoming a list.
ExBinary 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))

Binary Search Tree

Example

Short notes

Questions

Binary Search Tree

Example

Short notes

Questions