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Circular Linked List

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Circular Linked List

Don’t start Circular Linked List (cll) with jargon. Start with a ticket queue node. That is the whole point.

Circular Linked List (cll) on the board — head → next → …. Then say what a ticket queue node looks like after.

Circular Linked List (cll) exists so Vikram can keep a ticket queue node correct in a counter.

Circular Linked List (cll) shows up in a counter. Name a ticket queue node, not “a real-world scenario”.

If a ticket queue node breaks under Circular Linked List (cll), check losing the next pointer on delete first.

After Circular Linked List (cll), Vikram should still remember losing the next pointer on delete.

One breath for Circular Linked List (cll), then a ticket queue node, then losing the next pointer on delete. Sit down.

Diagram

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

Exam tip

Board: a ticket queue node. Dry-run Circular Linked List (cll). Name the trap: losing the next pointer on delete.

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 (cll) — a linked list chains nodes with next pointers instead of contiguous indexes.

Short notes

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