Doubly-Linked List LeetCode Problems: All 10, With Python Solutions

Every problem in this library that LeetCode tags Doubly-Linked List 10 in total, 7 of them with a complete Python solution, a worked example and the time and space complexity of the approach.

  • 10 problems
  • 0 Easy
  • 6 Medium
  • 4 Hard

How Doubly-Linked List problems are solved

A tag names the subject, not the method. These pattern hubs cover the techniques that actually solve Doubly-Linked List problems — each one explains the approach, gives a Python template and states its complexity.

  • Linked List — Rewire pointers in place, with a dummy head and a saved next to keep it safe.

Doubly-Linked List problems by difficulty

Problems with a complete Python solution are listed first, then by ascending problem number.

Medium (6)

#ProblemDifficultyTopics
146LRU CacheMediumDesign, Hash Table, Linked List +1
430Flatten a Multilevel Doubly Linked ListMediumDepth-First Search, Linked List, Doubly-Linked List
1472Design Browser HistoryMediumStack, Design, Array +3
1797Design Authentication ManagerMediumDesign, Hash Table, Linked List +1
426Convert Binary Search Tree to Sorted Doubly Linked ListPremiumMediumStack, Tree, Depth-First Search +4
1756Design Most Recently Used QueuePremiumMediumDesign, Array, Linked List +3

Hard (4)

#ProblemDifficultyTopics
432All O`one Data StructureHardDesign, Hash Table, Linked List +1
460LFU CacheHardDesign, Hash Table, Linked List +1
2296Design a Text EditorHardStack, Design, Linked List +3
716Max StackPremiumHardStack, Design, Linked List +2

When the Doubly-Linked List problem arrives live

Stealth Interview is a desktop app for macOS and Windows. It reads the coding problem off your screen, returns a working solution with a step-by-step explanation and its time and space complexity, and transcribes what the interviewer is saying — while staying invisible to screen sharing.