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Linked List

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Linked List

If you can teach Linked List using a ticket queue node, you know it. If you only know the heading, you don’t.

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

Skip Linked List and losing the next pointer on delete shows up in a counter.

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

Linked List trap — losing the next pointer on delete. Asha loses marks for that every viva.

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

Close 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 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

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

Short notes

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

Linked List

Example

Short notes

Questions

Linked List

Example

Short notes

Questions