Spotify Coding Interview Questions
31 Spotify coding interview problems with full optimal solutions — 22 easy, 7 medium, 2 hard. Every problem ships with multiple approaches (brute-force first, then the optimal), complexity tables for each, company-specific tips on what an Spotify interviewer values, and a FAQ section.
Showing 31 problems of 31
- #19easyfoundational
19. Top K Frequent Elements
Given an integer array, return the k most frequent elements — a canonical heap pattern that maps directly to how Spotify surfaces the top-K tracks on a Weekly Charts leaderboard.
- #20easyfoundational
20. Kth Largest Element in an Array
Find the kth largest value in an unsorted array — Spotify uses this pattern when ranking the 50th-percentile stream count across a catalog of millions of tracks.
- #21easyfoundational
21. Longest Common Prefix
Find the longest common prefix string among an array of strings — the trie-based thinking here mirrors how Spotify's search autocomplete narrows song and artist suggestions as you type.
- #22easyfoundational
22. Number of Islands
Count connected components in a 2-D grid using BFS/DFS — a graph traversal warm-up that Spotify applies to connected-artist clustering in recommendation graphs.
- #23mediumfoundational
23. Longest Substring Without Repeating Characters
Find the longest window of unique characters in a string — the sliding-window technique translates directly to computing rolling unique-listener counts across a time-series of Spotify stream events.
- #24mediumfoundational
24. LRU Cache
Design a cache that evicts the least-recently-used item when capacity is exceeded — exactly the structure Spotify uses to keep the most recently played tracks resident in memory without re-fetching from object storage.
- #25mediumfoundational
25. Coin Change
Find the minimum number of coins to reach a target amount — a bottom-up DP pattern Spotify applies to cost-minimization in dynamic ad-insertion and playlist-segment composition problems.
- #26mediumfoundational
26. Course Schedule
Determine whether all courses can be finished given prerequisite pairs — cycle detection in a directed graph, mirroring how Spotify validates dependency ordering in its microservice deployment pipeline.
- #27mediumfoundational
27. Find Median from Data Stream
Return the running median as numbers arrive one-by-one using two heaps — a pattern Spotify uses to compute real-time median session-length or track-duration statistics across millions of concurrent streams.
- #28mediumfoundational
28. Word Break
Determine if a string can be segmented into dictionary words using DP — a tokenisation technique Spotify applies in NLP preprocessing of lyrics and podcast transcripts before feeding text to recommendation models.
- #29mediumfoundational
29. Graph Valid Tree
Determine whether n nodes and given edges form a valid tree — union-find cycle detection that Spotify applies when validating artist-collaboration graphs to ensure no circular attribution loops exist.
- #30hardfoundational
30. Merge K Sorted Lists
Merge k sorted linked lists into one sorted list — a priority-queue pattern that maps to how Spotify merges sorted event streams from multiple data-pipeline shards when reconstructing a global play-history timeline.
- #31hardfoundational
31. Word Ladder
Find the shortest transformation sequence from one word to another changing one letter at a time — BFS on an implicit graph that mirrors Spotify's genre-to-genre shortest-path queries in its music taxonomy graph.
- #1easyfoundational
1. Two Sum
Given an array of integers and a target, return indices of two numbers that sum to the target.
- #2easyfoundational
2. Valid Parentheses
Determine if a string of brackets is balanced with proper nesting.
- #3easyfoundational
3. Merge Two Sorted Lists
Merge two sorted linked lists into one sorted list.
- #4easyfoundational
4. Remove Duplicates from Sorted Array
Remove duplicates in place from a sorted array and return the new length.
- #5easyfoundational
5. Remove Element
Remove all occurrences of a target value in place and return the new length.
- #6easyfoundational
6. Search Insert Position
Find the index where a target should be inserted in a sorted array.
- #7easyfoundational
7. Plus One
Increment a large integer represented as a digit array by one.
- #8easyfoundational
8. Merge Sorted Array
Merge nums2 into nums1 in place where nums1 has space at the end.
- #9easyfoundational
9. Binary Tree Inorder Traversal
Return the inorder traversal of a binary tree.
- #10easyfoundational
10. Same Tree
Determine if two binary trees are structurally identical with equal values.
- #11easyfoundational
11. Symmetric Tree
Determine if a binary tree is a mirror image of itself around the center.
- #12easyfoundational
12. Maximum Depth of Binary Tree
Find the maximum depth of a binary tree.
- #13easyfoundational
13. Balanced Binary Tree
Check if a binary tree is height balanced.
- #14easyfoundational
14. Minimum Depth of Binary Tree
Find the minimum number of nodes along the shortest path from root to a leaf.
- #15easyfoundational
15. Path Sum
Determine if the tree has a root-to-leaf path that sums to a target.
- #16easyfoundational
16. Pascal's Triangle
Generate the first numRows of Pascal's Triangle.
- #17easyfoundational
17. Best Time to Buy and Sell Stock
Find the maximum profit from one buy and one sell of a stock.
- #18easyfoundational
18. Valid Palindrome
Determine if a string is a palindrome considering only alphanumeric characters case-insensitively.