Leetcode Problem 24. Swap Nodes in Pairs

24. Swap Nodes in Pairs

Leetcode Solutions

Iterative Approach for Swapping Nodes in Pairs

  1. Initialize dummy as a new ListNode that points to head.
  2. Set prevNode to dummy.
  3. While firstNode and firstNode.next (which will be secondNode) are not null: a. Save firstNode.next in secondNode. b. Perform the swap by updating firstNode.next to secondNode.next and secondNode.next to firstNode. c. Update prevNode.next to secondNode to maintain the list's integrity. d. Move prevNode to firstNode. e. Update firstNode to firstNode.next (the next pair's first node).
  4. Return dummy.next, which is the new head of the swapped list.
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Recursive Approach for Swapping Nodes in Pairs

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