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Detect loop in a Linked list

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Detect loop in a Linked list

Detect loop in a Linked list is simple if you keep it on paper. Sara uses it for a ticket queue node in a counter.

Detect loop in a Linked list on the board: head → next → …. Then say what a ticket queue node looks like after.

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

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

Detect loop in a Linked list trap — losing the next pointer on delete. Sara loses marks for that every viva.

Detect loop in a Linked list is not a lonely heading. Sara ties it to a ticket queue node.

One breath for Detect loop in a Linked list, then a ticket queue node, then losing the next pointer on delete. Sit down.

Diagram

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

Exam tip

For Detect loop in a 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

Detect loop in a Linked list — a linked list chains nodes with next pointers instead of contiguous indexes.

Short notes

DefDetect loop in a Linked list — Sara uses it for a ticket queue node in a counter.
RuleDetect loop in a Linked list → head → next → ….
RememberDetect loop in a Linked list + time vs memory (a counter).
UseDetect loop in a Linked list in a counter (a ticket queue node).
TrapDetect loop in a Linked list — losing the next pointer on delete.
ExDetect loop in a 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

Detect loop in a Linked list

Example

Short notes

Questions

Detect loop in a Linked list

Example

Short notes

Questions