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Circular Linked List

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Circular Linked List

Circular Linked List sits in a counter. Vikram’s job is a ticket queue node. Write that first.

For Circular Linked List, time vs memory is in play. Don’t blame it until you have traced a ticket queue node.

Without Circular Linked List, a counter gets messy and a ticket queue node is hard to trust.

Use Circular Linked List when a ticket queue node must stay clear. If a simpler DSA step works, use that instead.

Don’t do this with Circular Linked List — losing the next pointer on delete. Interviewers spot it in ten seconds.

Place Circular Linked List next to nearby DSA work — head → next → … is the link.

Viva for Circular Linked List — what it is → head → next → … → the mistake (losing the next pointer on delete).

Diagram

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

Exam tip

For Circular 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

Circular Linked List — a linked list chains nodes with next pointers instead of contiguous indexes.

Short notes

DefCircular Linked List — Vikram uses it for a ticket queue node in a counter.
RuleCircular Linked List → head → next → ….
RememberCircular Linked List + time vs memory (a counter).
UseCircular Linked List in a counter (a ticket queue node).
TrapCircular Linked List — losing the next pointer on delete.
ExCircular 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

Circular Linked List

Example

Short notes

Questions

Circular Linked List

Example

Short notes

Questions