DSA · Theory

Memory efficient doubly linked list

Theory

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Memory efficient doubly linked list

Memory efficient doubly linked list sits in a counter. Vikram’s job is a ticket queue node. Write that first.

For Memory efficient doubly linked list, time vs memory is in play. Don’t blame it until you have traced a ticket queue node.

Without Memory efficient doubly linked list, a counter gets messy and a ticket queue node is hard to trust.

Memory efficient doubly linked list shows up in a counter. Name a ticket queue node, not “a real-world scenario”.

Memory efficient doubly linked list trap: losing the next pointer on delete. Vikram loses marks for that every viva.

Place Memory efficient doubly linked list next to nearby DSA work — head → next → … is the link.

Close Memory efficient doubly 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 Memory efficient doubly 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

Memory efficient doubly linked list — a linked list chains nodes with next pointers instead of contiguous indexes.

Short notes

DefMemory efficient doubly linked list — Vikram uses it for a ticket queue node in a counter.
RuleMemory efficient doubly linked list → head → next → ….
RememberMemory efficient doubly linked list + time vs memory (a counter).
UseMemory efficient doubly linked list in a counter (a ticket queue node).
TrapMemory efficient doubly linked list — losing the next pointer on delete.
ExMemory efficient doubly 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

Memory efficient doubly linked list

Example

Short notes

Questions

Memory efficient doubly linked list

Example

Short notes

Questions