DSA · Theory

Detect and Remove Loop in a Linked List

Theory

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Detect and Remove Loop in a Linked List

Priya only reaches for Detect and Remove Loop in a Linked List when a ticket queue node has to stay correct in a counter.

Detect and Remove Loop in a Linked List on the board: head → next → …. Then say what a ticket queue node looks like after.

Without Detect and Remove Loop in a Linked List, a counter gets messy and a ticket queue node is hard to trust.

Detect and Remove Loop in a Linked List shows up in a counter. Name a ticket queue node, not “a real-world scenario”.

Detect and Remove Loop in a Linked List trap: losing the next pointer on delete. Priya loses marks for that every viva.

Place Detect and Remove Loop in a Linked List next to nearby DSA work — head → next → … is the link.

Close Detect and Remove Loop in a Linked List with: “If I skip it, a ticket queue node goes wrong like this: losing the next pointer on delete.”

Diagram

  [10] → [20] → [30] → /
   head              tail

Exam tip

For Detect and Remove Loop in a Linked List: definition + a counter + one failure.

Example

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

head = Node(1, Node(2, Node(3)))
cur = head
while cur:
    print(cur.val, end=" -> " if cur.next else "\n")
    cur = cur.next

Detect and Remove Loop in a Linked List — a linked list chains nodes with next pointers instead of contiguous indexes.

Short notes

DefDetect and Remove Loop in a Linked List — Priya uses it for a ticket queue node in a counter.
RuleDetect and Remove Loop in a Linked List → head → next → ….
RememberDetect and Remove Loop in a Linked List + time vs memory (a counter).
UseDetect and Remove Loop in a Linked List in a counter (a ticket queue node).
TrapDetect and Remove Loop in a Linked List — losing the next pointer on delete.
ExDetect and Remove Loop in a Linked List → a ticket queue node.

class Node: def __init__(self, val, next=None): self.val = val self.next = next head = Node(1, Node(2, Node(3))) cur = head while cur: print(cur.val, end=" -> " if cur.next else "\n") cur = cur.next

Detect and Remove Loop in a Linked List

Example

Short notes

Questions

Detect and Remove Loop in a Linked List

Example

Short notes

Questions