Pointer mutation [mp]

Micro pattern¶

Description¶

Change links between existing nodes while preserving references needed to continue or reconnect traversal.

Problems¶

Delete or bypass nodes¶

Redirect a predecessor around a removed node.

• 19. Remove Nth Node From End of List (Top Easy)
• 237. Delete Node in a Linked List (Top Easy)

Merge or rearrange nodes¶

Preserve successor references while reconnecting nodes into a desired order.

• 21. Merge Two Sorted Lists (Top Easy)
• 206. Reverse Linked List (Top Easy)
• 234. Palindrome Linked List (Top Easy)
• 328. Odd Even Linked List (Top Medium)
• 23. Merge k Sorted Lists (Top Hard)
• 138. Copy List with Random Pointer (Top Hard)
• 148. Sort List (Top Hard)
• Insertion sort linked list (DSA)
• Bottom-up merge sort linked list (DSA)
• Top-down merge sort linked list (DSA)
• AVL trees (DSA)
• 669. Trim a Binary Search Tree (Google Prep)

Populate additional links¶

Set horizontal links while preserving child links.

• 116. Populating Next Right Pointers in Each Node (Top Medium)

Maintain doubly linked ordering¶

Update both neighboring links during removal and reinsertion.

• 146. LRU Cache (Top Hard)