Coding interview questions

Apple Coding Interview Questions (DSA)

The 50 DSA problems Apple has asked most in the last six months, most-asked first. 50 of them have a full breakdown with diagrams and code. Tick them off as you go.

Practice a Apple interview with me

I'm Alex. I'll pick 2 problems from Apple's list at your level and interview you like a real Apple round.

50problems
50full breakdowns
49topics

By difficulty: Easy (7) · Medium (36) · Hard (7)

Start Apple Mock Interview→

Topics

49.Group Anagrams
Full breakdownArrayHash TableString
Medium+9▶ Mock
1146.Snapshot Array
Full breakdownArrayHash TableBinary Search
Medium▶ Mock
1143.Longest Common Subsequence
Full breakdownStringDynamic ProgrammingLongest Common Subsequence
Medium▶ Mock
198.House Robber
Full breakdownArrayDynamic Programming
Medium+1▶ Mock
857.Minimum Cost to Hire K Workers
Full breakdownArrayGreedySorting
2402.Meeting Rooms III
Full breakdownArrayHash TableSorting
1049.Last Stone Weight II
Full breakdownArrayDynamic ProgrammingKnapsack Problem
Medium▶ Mock
1046.Last Stone Weight
Full breakdownArrayHeap (Priority Queue)
713.Subarray Product Less Than K
Full breakdownArrayBinary SearchSliding Window
Medium▶ Mock
127.Word Ladder
Full breakdownHash TableStringBreadth-First Search
146.LRU Cache
Full breakdownHash TableLinked ListDesign
Medium+9▶ Mock
56.Merge Intervals
Full breakdownArraySortingQuicksort
Medium+14▶ Mock
362.Design Hit Counter
Full breakdownArrayBinary SearchDesign
Medium▶ Mock
1.Two Sum
Full breakdownArrayHash Table
Easy+10▶ Mock
210.Course Schedule II
Full breakdownDepth-First SearchBreadth-First SearchGraph Theory
Medium+3▶ Mock
380.Insert Delete GetRandom O(1)
Full breakdownArrayHash TableMath
Medium▶ Mock
121.Best Time to Buy and Sell Stock
Full breakdownArrayDynamic Programming
Easy+10▶ Mock
14.Longest Common Prefix
Full breakdownArrayStringTrie
Easy+2▶ Mock
15.3Sum
Full breakdownArrayTwo PointersSorting
Medium+5▶ Mock
2502.Design Memory Allocator
Full breakdownArrayHash TableDesign
Medium+1▶ Mock
981.Time Based Key-Value Store
Full breakdownHash TableStringBinary Search
Medium+1▶ Mock
128.Longest Consecutive Sequence
Full breakdownArrayHash TableUnion-Find
Medium+3▶ Mock
621.Task Scheduler
Full breakdownArrayHash TableGreedy
Medium+2▶ Mock
670.Maximum Swap
Full breakdownMathGreedy
Medium▶ Mock
785.Is Graph Bipartite?
Full breakdownDepth-First SearchBreadth-First SearchUnion-Find
Medium▶ Mock
3.Longest Substring Without Repeating Characters
Full breakdownHash TableStringSliding Window
Medium+13▶ Mock
678.Valid Parenthesis String
Full breakdownStringDynamic ProgrammingStack
Medium▶ Mock
3408.Design Task Manager
Full breakdownHash TableDesignHeap (Priority Queue)
Medium▶ Mock
200.Number of Islands
Full breakdownArrayDepth-First SearchBreadth-First Search
Medium+7▶ Mock
283.Move Zeroes
Full breakdownArrayTwo Pointers
460.LFU Cache
Full breakdownHash TableLinked ListDesign
Hard+1▶ Mock
23.Merge k Sorted Lists
Full breakdownLinked ListDivide and ConquerHeap (Priority Queue)
Hard+4▶ Mock
36.Valid Sudoku
Full breakdownArrayHash TableMatrix
Medium▶ Mock
207.Course Schedule
Full breakdownDepth-First SearchBreadth-First SearchGraph Theory
Medium+4▶ Mock
125.Valid Palindrome
Full breakdownTwo PointersString
347.Top K Frequent Elements
Full breakdownArrayHash TableDivide and Conquer
Medium+6▶ Mock
206.Reverse Linked List
Full breakdownLinked ListRecursion
Easy+4▶ Mock
54.Spiral Matrix
Full breakdownArrayMatrixSimulation
Medium+2▶ Mock
122.Best Time to Buy and Sell Stock II
Full breakdownArrayDynamic ProgrammingGreedy
Medium▶ Mock
48.Rotate Image
Full breakdownArrayMathMatrix
Medium▶ Mock
227.Basic Calculator II
Full breakdownMathStringStack
Medium▶ Mock
5.Longest Palindromic Substring
Full breakdownTwo PointersStringDynamic Programming
Medium+8▶ Mock
4.Median of Two Sorted Arrays
Full breakdownArrayBinary SearchDivide and Conquer
Hard+5▶ Mock
560.Subarray Sum Equals K
Full breakdownArrayHash TablePrefix Sum
Medium+2▶ Mock
428.Serialize and Deserialize N-ary Tree
Full breakdownStringTreeDepth-First Search
567.Permutation in String
Full breakdownHash TableTwo PointersString
Medium▶ Mock
314.Binary Tree Vertical Order Traversal
Full breakdownHash TableTreeDepth-First Search
Medium▶ Mock
17.Letter Combinations of a Phone Number
Full breakdownHash TableStringBacktracking
Medium+1▶ Mock
72.Edit Distance
Full breakdownStringDynamic Programming
Medium▶ Mock

Frequently Asked Questions

What questions does Apple ask in coding interviews?

Apple coding interviews focus on 0-1 Knapsack, Array, Backtracking, Bidirectional Search, and other data structure problems. We compiled 50 questions from real Apple interviews. The most common topics are 0-1 Knapsack, Array, Backtracking, Bidirectional Search, Binary Search. Filter by topic to see what comes up most often.

How many Apple coding interview questions are there?

InterviewSkool has 50 Apple coding interview questions: 7 Easy, 36 Medium, and 7 Hard. Most Apple interviews focus on Medium-difficulty problems, so prioritize those in your prep.

How should I prepare for Apple coding interviews?

Start with Medium difficulty problems. Group by topic (Array, Tree, DP) to build pattern recognition. Aim to solve 30 to 40 problems before your interview. Then practice under pressure with a mock interview.

Are Apple coding interview questions free?

Yes. All 50 Apple coding interview questions are free to browse with no sign-up required. You can filter by difficulty and topic tags. Start a mock interview with a free credit to practice under real pressure.

Practice with a Mock Interview

Simulate real Apple interview pressure with our AI interviewer.

Start Mock Interview →