DSA · Theory

Inorder predecessor and successor for a given key in BST

Theory

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Inorder predecessor and successor for a given key in BST

If you can teach Inorder predecessor and successor for a given key in BST using folder on disk, you know it. If you only know the heading, you don’t.

Inorder predecessor and successor for a given key in BST order: meaning → left < root < right → one limit. Dumping ten features helps nobody.

Without Inorder predecessor and successor for a given key in BST, a file explorer gets messy and folder on disk is hard to trust.

Priya ships Inorder predecessor and successor for a given key in BST in a file explorer. That is the use case worth saying.

Inorder predecessor and successor for a given key in BST trap: unbalanced BST becoming a list. Priya loses marks for that every viva.

Inorder predecessor and successor for a given key in BST is not a lonely heading. Priya ties it to folder on disk.

One breath for Inorder predecessor and successor for a given key in BST, then folder on disk, then unbalanced BST becoming a list. Sit down.

Diagram

Exam tip

Say Inorder predecessor and successor for a given key in BST in one breath, then left < root < right, then unbalanced BST becoming a list.

Example

class Node:
    def __init__(self, val):
        self.val = val
        self.left = None
        self.right = None

def insert(root, val):
    if root is None:
        return Node(val)
    if val < root.val:
        root.left = insert(root.left, val)
    elif val > root.val:
        root.right = insert(root.right, val)
    return root

root = None
for v in [5, 2, 7, 1]:
    root = insert(root, v)
print(root.val, root.left.val, root.right.val)

Inorder predecessor and successor for a given key in BST — bST invariant: left < node < right — enables log-time search when balanced.

Short notes

DefInorder predecessor and successor for a given key in BST — Priya uses it for folder on disk in a file explorer.
RuleInorder predecessor and successor for a given key in BST → left < root < right.
RememberInorder predecessor and successor for a given key in BST + time vs memory (a file explorer).
UseInorder predecessor and successor for a given key in BST in a file explorer (folder on disk).
TrapInorder predecessor and successor for a given key in BST — unbalanced BST becoming a list.
ExInorder predecessor and successor for a given key in BST → folder on disk.

class Node: def __init__(self, val): self.val = val self.left = None self.right = None def insert(root, val): if root is None: return Node(val) if val < root.val: root.left = insert(root.left, val) elif val > root.val: root.right = insert(root.right, val) return root root = None for v in [5, 2, 7, 1]: root = insert(root, v) print(root.val, root.left.val, root.right.val)

Inorder predecessor and successor for a given key in BST

Example

Short notes

Questions

Inorder predecessor and successor for a given key in BST

Example

Short notes

Questions