PRACTICE

Design Interview Questions

46 Design problems asked across FAANG and top tech companies. Approach hints, optimal solutions, and related problems.

Ready to try these in a real interview?

I'm Alex. I'll interview you on 2 problems like these at your level, ask follow-ups, and give you a scored report.

Start mock with Alex
🔒

to save your progress.

Companies

Topics

Design 46
DesignClear all
146.LRU Cache
Hash TableLinked ListDesign
Medium+9▶ Mock
Implement Trie (Prefix Tree)
TrieDesignString
Medium+2▶ Mock
Design Add and Search Words Data Structure
TrieDepth-First SearchDesign
Medium+1▶ Mock
295.Find Median from Data Stream
HeapDesignData Stream
Hard+6▶ Mock
297.Serialize and Deserialize Binary Tree
Depth-First SearchBreadth-First SearchTree
Hard+4▶ Mock
460.LFU Cache
Hash TableLinked ListDesign
Hard+1▶ Mock
1146.Snapshot Array
ArrayHash TableBinary Search
Medium▶ Mock
341.Flatten Nested List Iterator
StackTreeDepth-First Search
Medium▶ Mock
981.Time Based Key-Value Store
Hash TableStringBinary Search
Medium+1▶ Mock
380.Insert Delete GetRandom O(1)
ArrayHash TableMath
Medium▶ Mock
2502.Design Memory Allocator
ArrayHash TableDesign
Medium+1▶ Mock
362.Design Hit Counter
ArrayBinary SearchDesign
Medium▶ Mock
155.Min Stack
StackDesign
Medium▶ Mock
2408.Design SQL
ArrayHash TableString
Medium▶ Mock
1429.First Unique Number
ArrayHash TableDesign
Medium▶ Mock
303.Range Sum Query - Immutable
ArrayDesignPrefix Sum
Easy▶ Mock
1797.Design Authentication Manager
Hash TableLinked ListDesign
Medium▶ Mock
359.Design Logger Rate Limiter
Hash TableDesignData Stream
Easy▶ Mock
2034.Stock Price Fluctuation
Hash TableDesignHeap
Medium▶ Mock
3484.Design Spreadsheet
ArrayHash TableString
Medium▶ Mock
631.Design Excel Sum Formula
ArrayHash TableString
Hard▶ Mock
900.RLE Iterator
ArrayDesignCounting
Medium▶ Mock
432.All O'one Data Structure
Hash TableLinked ListDesign
Hard▶ Mock
2276.Count Integers in Intervals
DesignSegment TreeOrdered Set
Hard▶ Mock
2353.Design a Food Rating System
ArrayHash TableString
Medium▶ Mock
2296.Design a Text Editor
Linked ListStringStack
Hard▶ Mock
588.Design In-Memory File System
Hash TableStringDesign
Hard▶ Mock
3829.Design Ride Sharing System
Hash TableDesignQueue
Medium▶ Mock
353.Design Snake Game
ArrayHash TableDesign
Medium▶ Mock
3408.Design Task Manager
Hash TableDesignHeap
Medium▶ Mock
348.Design Tic-Tac-Toe
ArrayHash TableDesign
Medium▶ Mock
1396.Design Underground System
Hash TableStringDesign
Medium▶ Mock
271.Encode and Decode Strings
ArrayStringDesign
Medium▶ Mock
933.Number of Recent Calls
DesignQueueData Stream
Easy▶ Mock
716.Max Stack
Linked ListStackDesign
Hard▶ Mock
384.Shuffle an Array
ArrayMathDesign
Medium▶ Mock
Design Add and Search Words Data Structure
StringDepth-First SearchDesign
Medium▶ Mock
244.Shortest Word Distance II
ArrayHash TableTwo Pointers
Medium▶ Mock
381.Insert Delete GetRandom O(1) - Duplicates allowed
ArrayHash TableMath
Hard▶ Mock
622.Design Circular Queue
ArrayLinked ListDesign
Medium▶ Mock
642.Design Search Autocomplete System
StringDepth-First SearchDesign
Hard▶ Mock
706.Design HashMap
ArrayHash TableLinked List
Easy▶ Mock
1244.Design A Leaderboard
Hash TableDesignSorting
Medium▶ Mock
1352.Product of the Last K Numbers
ArrayMathDesign
Medium▶ Mock
1600.Throne Inheritance
Hash TableTreeDepth-First Search
Medium▶ Mock
2043.Simple Bank System
ArrayHash TableDesign
Medium▶ Mock

Practice with a Mock Interview

Solve these Design problems under real interview pressure with our AI interviewer.

Start Mock Interview →