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Given a linked list L with integer keys, you need to remove nodes with duplicate absolute key values. That is, for each key K, only the first node with absolute value K is kept. Meanwhile, all removed nodes must be saved in another linked list. For example, given L as 21→-15→-15→-7→15, you should output the deduplicated list 21→-15→-7 and the r ...

1. The time complexity of an algorithm primarily depends on ( ). A. Problem size B. CPU clock speed C. Source code length D. Quality of the compiled binary Answer: A 2. For a sequential list containing n elements, inserting a new element while preserving the existing order requires shifting ( ) elements on average. A. n B. n/2 C. 2n D. n² Answe ...

Swappnig Adjacent Nodes in Pairs Given a linked list, swap every two adjacent nodes and return the head pointer. Only pointer manipulation is allowed; nodde values must remain unchanged. A sentinel node simplifies boundary handling. Maintain a prev pointer positioned immediately before each pair. In every iteration, identify the first node, the ...

Swapping Nodes in PairsApproach: Using a dummy head nodeLogic: Create a dummy head node to simplify the swapping process. Use a current pointer that moves forward two steps at a time. The loop continues as long as there are at least two more nodes to swap.Implementation:/** * Definition for singly-linked list. * struct ListNode { * int v ...

Remove Linked List Elements (LeetCode 203) Given the head of a linked list and an integer val, remove all nodes where Node.val == val and return the new head node. Using a dummy head simplifies handling edge cases, especially when the head node itself needs to be removed. A traversal pointer prev is used to point to the node preceding the one c ...

24. Swap Nodes in Pairs Problem: Swap adjacent nodes in a linked list pairwise, returnnig the new head. Do not modify node values—only rewire nodes. Approaches: Iterative: Use a dummy head to track the previous node. Adjust pointers for each pair. Recursive: Swap the first two nodes, then recurce on the reamining list. class Solution: ...