Reordering Linked Lists Techniques

The video tutorial explains how to solve the 'reorder list' problem for a singly linked list. The goal is to rearrange the list by alternating nodes from the start and end. The tutorial covers both solutions using extra space and an in-place solution. The in-place solution involves reversing the second half of the list and merging it with the first half. The tutorial provides a detailed explanation of the algorithm and a step-by-step coding demonstration.

What is the main goal when reordering a linked list in this problem?

• To reverse the entire list

• To alternate nodes from the start and end of the list

• To remove duplicate nodes

• To sort the list in ascending order

What is one method to reorder the list using extra space?

• Convert the list to a stack and reorder

• Use a hash map to store node positions

• Convert the list to an array and reorder

• Use a queue to reorder the list

What is the key challenge when reordering the list without extra space?

• Finding the length of the list

• Reversing the second half of the list

• Reversing the entire list

• Sorting the list

How do you determine the middle of the list in the in-place solution?

• By using a recursive function

• By counting the nodes

• Using a fast and slow pointer

• Using a single pointer

What is the purpose of reversing the second half of the list?

• To sort the list

• To facilitate merging with the first half

• To find the maximum value

• To remove duplicate nodes

What is the first step in merging the two halves of the list?

• Swap the first and last nodes

• Set the last node of the first half to null

• Reverse the first half

• Sort both halves

Why do we use temporary variables during the merge process?

• To calculate the sum of node values

• To save links before breaking them

• To keep track of node values

• To store the list length

What happens to the pointers during the merge process?

• They are reversed

• They are set to null

• They are shifted to the next nodes

• They are swapped

What is the final step after merging the two halves?

• Sort the list

• Ensure the last node points to null

• Print the list

• Return the new list

What is the time complexity of the in-place solution?

• O(n)

• O(1)

• O(log n)

• O(n^2)