Convert a doubly linked list into reversal anti clockwise spiral form
In this article, we will explore a fascinating algorithmic problem: converting a doubly linked list into a reversal anti-clockwise spiral form. We'll delve into the problem statement, walk through an illustrative example, outline the algorithmic approach, provide pseudocode, detail the algorithm's implementation, explain the resulting output, and analyze the time complexity of the solution.
Problem Statement
Given a doubly linked list, we are tasked with transforming it into a specific arrangement known as the reversal anti-clockwise spiral form. This form involves altering the links between nodes in such a way that the order of nodes in the list forms an anti-clockwise spiral pattern. Additionally, the direction of the doubly linked list should be reversed. The problem presents a unique challenge that combines linked list manipulation and spiral pattern creation.
Illustrative Example
Consider the following doubly linked list:
1 <-> 2 <-> 3 <-> 4 <-> 5 <-> 6 <-> 7 <-> 8 <-> 9
After converting the list into the reversal anti-clockwise spiral form, it will look like this:
5 <-> 4 <-> 6 <-> 3 <-> 7 <-> 2 <-> 8 <-> 1 <-> 9
This transformation involves reordering the nodes to create an anti-clockwise spiral pattern while reversing the direction of the list.
Algorithmic Approach
- Initialize pointers
current
andlast
to the head and tail of the linked list, respectively. - Set up auxiliary pointers to assist in link swapping.
- Begin converting the list:
- Swap links between
current
andlast
, considering the anti-clockwise spiral pattern. - Update pointers and auxiliary pointers as needed.
- Swap links between
- Reverse the entire linked list to complete the transformation.
Pseudocode
reversalAntiSpiral():
if head is null or head.next is null:
return
Initialize last = tail, current = head, auxiliary = null
Set up temp and back pointers
Set head as tail to start the new configuration
Loop until current and last pointers meet or cross:
Handle edge cases when current and last are adjacent
Swap links considering the anti-clockwise spiral
Update pointers and auxiliary pointers
Reverse the entire linked list using reverseNode()
reverseNode():
if head is null:
return
Initialize temp = head, back = null
Update tail as head
Traverse the list and modify links to reverse nodes
Main():
Initialize a doubly linked list (dll)
Insert nodes into the linked list
Display the list before the transformation
Convert the list to reversal anti-clockwise spiral form
Display the transformed list
Code Solution
-
1) Reversal anticlockwise spiral conversion of doubly linked list in java
2) Reversal anticlockwise spiral conversion of doubly linked list in c++
3) Reversal anticlockwise spiral conversion of doubly linked list in c
4) Reversal anticlockwise spiral conversion of doubly linked list in c#
5) Reversal anticlockwise spiral conversion of doubly linked list in php
6) Reversal anticlockwise spiral conversion of doubly linked list in python
7) Reversal anticlockwise spiral conversion of doubly linked list in ruby
8) Reversal anticlockwise spiral conversion of doubly linked list in scala
9) Reversal anticlockwise spiral conversion of doubly linked list in swift
10) Reversal anticlockwise spiral conversion of doubly linked list in kotlin
11) Reversal anticlockwise spiral conversion of doubly linked list in typescript
12) Reversal anticlockwise spiral conversion of doubly linked list in golang
13) Reversal anticlockwise spiral conversion of doubly linked list in vb.net
14) Reversal anticlockwise spiral conversion of doubly linked list in node js
Time Complexity Analysis
- The
reversalAntiSpiral
function iterates through the linked list once, performing constant-time operations per iteration. Therefore, its time complexity is O(n), where n is the number of nodes in the linked list. - The
reverseNode
function also traverses the entire linked list once, resulting in a time complexity of O(n).
Please share your knowledge to improve code and content standard. Also submit your doubts, and test case. We improve by your feedback. We will try to resolve your query as soon as possible.
New Comment