Doubly Linked List
Detailed guide and Python implementation for the 'Doubly Linked List' problem.
Problem Statement
Write a function create_doubly_linked_list(arr) that takes a list of integers arr, constructs a doubly linked list, and returns a tuple of two lists: (forward_traverse, backward_traverse) to verify that both the next and prev pointers are correctly configured.
- •0 <= len(arr) <= 1000
- •-10^4 <= arr[i] <= 10^4
Examples
arr = [1, 2, 3]
([1, 2, 3], [3, 2, 1])
Constructing the doubly linked list 1 <=> 2 <=> 3 allows traversing forward to get [1, 2, 3] and backward to get [3, 2, 1].
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
Ready to Solve?
Open the problem in PyRun's browser-based Python editor. Your code runs fully offline — no server required.
Recommended Python Resources
Expand your knowledge with related interactive tutorials, cheat sheets, and code comparisons.
Python Lists
Learn everything about Python lists. Discover how to create, slice, modify, and iterate through arrays in Python natively.
How to Sort a List in Python
Learn how to sort a list in Python using the sort() method and the sorted() function. Discover custom key sorting and reverse order examples.
Python List Methods
Quick reference guide for Python list operations. Master appending, inserting, removing, sorting, and slicing elements.
Python vs JavaScript: Which Programming Language is Best?
A comprehensive comparison between Python and JavaScript. Explore syntax differences, performance, use cases (backend vs frontend), and coding examples.