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Singly Linked List

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Singly Linked List

Don’t start Singly Linked List with jargon. Start with a ticket queue node. That is the whole point.

Singly Linked List order — meaning → head → next → … → one limit. Dumping ten features helps nobody.

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

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

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

Singly Linked List is not a lonely heading. Arun ties it to a ticket queue node.

One breath for Singly Linked List, 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 Singly Linked List. 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

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

Short notes

DefSingly Linked List — Arun uses it for a ticket queue node in a counter.
RuleSingly Linked List → head → next → ….
RememberSingly Linked List + a dry-run table (a counter).
UseSingly Linked List in a counter (a ticket queue node).
TrapSingly Linked List — losing the next pointer on delete.
ExSingly 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

Singly Linked List

Example

Short notes

Questions

Singly Linked List

Example

Short notes

Questions