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Linked List Operations

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Linked List Operations

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

Keep Linked List Operations small. Riya should finish a ticket queue node in a few lines, not a 40-line dump.

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

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

If a ticket queue node breaks under Linked List Operations, check losing the next pointer on delete first.

After Linked List Operations, Riya should still remember losing the next pointer on delete.

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

Diagram

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

Exam tip

Board: a ticket queue node. Dry-run Linked List Operations. 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

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

Short notes

DefLinked List Operations — Riya uses it for a ticket queue node in a counter.
RuleLinked List Operations → head → next → ….
RememberLinked List Operations + Big-O (a counter).
UseLinked List Operations in a counter (a ticket queue node).
TrapLinked List Operations — losing the next pointer on delete.
ExLinked List Operations → 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

Linked List Operations

Example

Short notes

Questions

Linked List Operations

Example

Short notes

Questions