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Inorder Predecessor and Successor in a Binary Search Tree

Theory

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Inorder Predecessor and Successor in a Binary Search Tree

Inorder Predecessor and Successor in a Binary Search Tree is a DSA idea you prove with folder on disk, not with a slogan.

Do Inorder Predecessor and Successor in a Binary Search Tree once by hand. left < root < right. Change one input. Say the new result out loud.

Inorder Predecessor and Successor in a Binary Search Tree exists so Neha can keep folder on disk correct in a file explorer.

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

Don’t do this with Inorder Predecessor and Successor in a Binary Search Tree: unbalanced BST becoming a list. Interviewers spot it in ten seconds.

Inorder Predecessor and Successor in a Binary Search Tree is not a lonely heading. Neha ties it to folder on disk.

One breath for Inorder Predecessor and Successor in a Binary Search Tree, then folder on disk, then unbalanced BST becoming a list. Sit down.

Diagram

Exam tip

For Inorder Predecessor and Successor in a 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))

Inorder Predecessor and Successor in a Binary Search Tree — binary search halves a sorted array each step — O(log n).

Short notes

DefInorder Predecessor and Successor in a Binary Search Tree — Neha uses it for folder on disk in a file explorer.
RuleInorder Predecessor and Successor in a Binary Search Tree → left < root < right.
RememberInorder Predecessor and Successor in a Binary Search Tree + Big-O (a file explorer).
UseInorder Predecessor and Successor in a Binary Search Tree in a file explorer (folder on disk).
TrapInorder Predecessor and Successor in a Binary Search Tree — unbalanced BST becoming a list.
ExInorder Predecessor and Successor in a 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))

Inorder Predecessor and Successor in a Binary Search Tree

Example

Short notes

Questions

Inorder Predecessor and Successor in a Binary Search Tree

Example

Short notes

Questions