DSA · Theory

Binary Search Tree Implementation

Theory

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Binary Search Tree Implementation

Binary Search Tree Implementation is a DSA topic. In plain words you use it for folder on disk in a file explorer. Don’t start with a slogan — start with that picture.

Smallest example: left < root < right. Type it, run it, and say what you see. If you can do that from memory, you know Binary Search Tree Implementation.

From the example next to this theory: Binary Search Tree Implementation — binary search halves a sorted array each step — O(log n).

Trap — unbalanced BST becoming a list. Fix that before you talk about advanced DSA.

Viva — what is Binary Search Tree Implementation? Then show left < root < right. Then name the trap.

Diagram

Exam tip

What is Binary Search Tree Implementation? Show this: left < root < right. 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))

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

Short notes

DefBinary Search Tree Implementation — folder on disk in a file explorer.
Ruleleft < root < right
Trapunbalanced BST becoming a list
Usea file explorer

DSA · Theory

Binary Search Tree Implementation

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Theory

276/810

Binary Search Tree Implementation

Binary Search Tree Implementation is a DSA topic. In plain words you use it for folder on disk in a file explorer. Don’t start with a slogan — start with that picture.

Smallest example: left < root < right. Type it, run it, and say what you see. If you can do that from memory, you know Binary Search Tree Implementation.

From the example next to this theory: Binary Search Tree Implementation — binary search halves a sorted array each step — O(log n).

Trap — unbalanced BST becoming a list. Fix that before you talk about advanced DSA.

Viva — what is Binary Search Tree Implementation? Then show left < root < right. Then name the trap.

Diagram

Exam tip

What is Binary Search Tree Implementation? Show this: left < root < right. 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))

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

Short notes

DefBinary Search Tree Implementation — folder on disk in a file explorer.
Ruleleft < root < right
Trapunbalanced BST becoming a list
Usea file explorer

Binary Search Tree Implementation

Example

Short notes

Questions

Binary Search Tree Implementation

Example

Short notes

Questions