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Reverse Alternate K nodes in a Singly Linked List

Theory

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Reverse Alternate K nodes in a Singly Linked List

Reverse Alternate K nodes in a Singly Linked List is a DSA idea you prove with a ticket queue node, not with a slogan.

Reverse Alternate K nodes in a Singly Linked List order: meaning → head → next → … → one limit. Dumping ten features helps nobody.

Skip Reverse Alternate K nodes in a Singly Linked List and losing the next pointer on delete shows up in a counter.

Rohit ships Reverse Alternate K nodes in a Singly Linked List in a counter. That is the use case worth saying.

Reverse Alternate K nodes in a Singly Linked List miss: losing the next pointer on delete. Fix it before you talk about advanced DSA.

After Reverse Alternate K nodes in a Singly Linked List, Rohit should still remember losing the next pointer on delete.

One breath for Reverse Alternate K nodes in a 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

For Reverse Alternate K nodes in a Singly 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

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

Short notes

DefReverse Alternate K nodes in a Singly Linked List — Rohit uses it for a ticket queue node in a counter.
RuleReverse Alternate K nodes in a Singly Linked List → head → next → ….
RememberReverse Alternate K nodes in a Singly Linked List + a dry-run table (a counter).
UseReverse Alternate K nodes in a Singly Linked List in a counter (a ticket queue node).
TrapReverse Alternate K nodes in a Singly Linked List — losing the next pointer on delete.
ExReverse Alternate K nodes in a Singly 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

Reverse Alternate K nodes in a Singly Linked List

Example

Short notes

Questions

Reverse Alternate K nodes in a Singly Linked List

Example

Short notes

Questions