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Triply Linked list

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Triply Linked list

Triply Linked list sits in a counter. Arun’s job is a ticket queue node. Write that first.

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

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

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

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

After Triply Linked list, Arun should still remember losing the next pointer on delete.

Close Triply 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 Triply 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

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

Short notes

DefTriply Linked list — Arun uses it for a ticket queue node in a counter.
RuleTriply Linked list → head → next → ….
RememberTriply Linked list + time vs memory (a counter).
UseTriply Linked list in a counter (a ticket queue node).
TrapTriply Linked list — losing the next pointer on delete.
ExTriply 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

Triply Linked list

Example

Short notes

Questions

Triply Linked list

Example

Short notes

Questions