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Construct a linked list from 2D matrix

Theory

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Construct a linked list from 2D matrix

Construct a linked list from 2D matrix (alt) is a DSA idea you prove with a ticket queue node, not with a slogan.

Construct a linked list from 2D matrix (alt) on the board: head → next → …. Then say what a ticket queue node looks like after.

Skip Construct a linked list from 2D matrix (alt) and losing the next pointer on delete shows up in a counter.

Dev ships Construct a linked list from 2D matrix (alt) in a counter. That is the use case worth saying.

Don’t do this with Construct a linked list from 2D matrix (alt): losing the next pointer on delete. Interviewers spot it in ten seconds.

Construct a linked list from 2D matrix (alt) is not a lonely heading. Dev ties it to a ticket queue node.

Viva for Construct a linked list from 2D matrix (alt): what it is → head → next → … → the mistake (losing the next pointer on delete).

Diagram

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

Exam tip

For Construct a linked list from 2D matrix (alt): 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

Construct a linked list from 2D matrix (alt) — a linked list chains nodes with next pointers instead of contiguous indexes.

Short notes

DefConstruct a linked list from 2D matrix (alt) — Dev uses it for a ticket queue node in a counter.
RuleConstruct a linked list from 2D matrix (alt) → head → next → ….
RememberConstruct a linked list from 2D matrix (alt) + Big-O (a counter).
UseConstruct a linked list from 2D matrix (alt) in a counter (a ticket queue node).
TrapConstruct a linked list from 2D matrix (alt) — losing the next pointer on delete.
ExConstruct a linked list from 2D matrix (alt) → 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

Construct a linked list from 2D matrix

Example

Short notes

Questions

Construct a linked list from 2D matrix

Example

Short notes

Questions