Coding & Algorithms interview questions

Showing 2851–2880 of 3276 results

• Find length of longest common subsequenceMedium

  This problem tests your ability to identify overlapping subproblems and optimal substructure by implementing a dynamic programming solution to find the length of the Longest Common Subsequence (LCS) between two strings.

  TikTokMachine Learning EngineerCoding & AlgorithmsTechnical Screen
• Find longest common subsequence lengthMedium

  This question tests the ability to solve the Longest Common Subsequence (LCS) problem using dynamic programming, specifically focusing on building a 2D state table.

  TikTokSoftware EngineerCoding & AlgorithmsOnsite
• Find longest substring with ≥k repeatsHard

  This problem tests your ability to use the sliding window technique combined with frequency maps to find the longest substring containing characters that each appear at least k times.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Find longest substring without repeating charactersMedium

  This question evaluates proficiency in string processing, duplicate-detection using appropriate data structures, and algorithmic complexity analysis within the Coding & Algorithms domain.

  TikTokMachine Learning EngineerCoding & AlgorithmsOnsite
• Find start indices of anagram substringsEasy

  This question evaluates proficiency in string processing, frequency-based pattern matching, and algorithmic efficiency under length constraints, testing the ability to reason about time and space trade-offs for substring searches.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Find the Longest Substring with at Most Two Distinct CharactersMedium

  Tests the ability to use the sliding window technique combined with a hash map to maintain a dynamic character set and determine the maximum length of a valid substring in linear time.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Fix a BST with two misplaced keysMedium

  This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Fix a BST with two misplaced keys states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  TikTokMachine Learning EngineerCoding & AlgorithmsTechnical Screen
• Flatten object & Promise.allMedium

  This question evaluates proficiency in JavaScript data manipulation and asynchronous programming, testing competencies in transforming nested objects into single-level key paths and reproducing Promise.all semantics.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Generate all safe queen placements on boardHard

  This question evaluates algorithm design for constraint-satisfaction problems, testing skills in search, recursion, backtracking, combinatorics, and state-space pruning.

  TikTokMachine Learning EngineerCoding & AlgorithmsTechnical Screen
• Implement Hash Map OperationsMedium

  Build a hash map behind a deterministic operation stream with insertion, replacement, lookup, removal, and missing-key behavior. The specification avoids built-in map storage and fixes return ordering and value bounds for a future portable console implementation.

  TikTokBackend Software EngineerCoding & AlgorithmsOnsite
• Implement K-means and run two iterationsMedium

  This question evaluates understanding of k-means clustering concepts (k-means++ initialization, Lloyd iterations, and SSE) and proficiency in numerical implementation and vectorized array operations.

  TikTokData ScientistCoding & AlgorithmsTechnical Screen
• Implement O(1) randomized multisetMedium

  Implement O(1) randomized multiset evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Implement a match-3 board resolverMedium

  TikTok software-engineer technical-screen coding question: implement a match-3 board resolver over an m×n grid. Repeatedly remove connected horizontal/vertical runs of three or more equal cells, apply gravity so survivors fall and blanks rise to the top, cascade until the board is stable, and return the final board plus the total cells removed. It tests grid simulation, run detection via linear scans, per-column gravity, termination reasoning, and time/space complexity analysis.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Implement an LRU cacheEasy

  This question tests the ability to implement a Least Recently Used (LRU) cache using a combination of a hash map and a doubly linked list to achieve constant time complexity for core operations.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Implement binary tree in-order traversalMedium

  This question evaluates understanding of binary tree traversal, comparing recursive and iterative (explicit stack) implementations and their time and space complexity. Commonly asked in Coding & Algorithms interviews to assess both practical implementation and conceptual understanding of tree data structures, algorithmic trade-offs, and complexity analysis.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Implement local maxima, bagging, and k-meansHard

  This problem tests your ability to implement a sliding window peak detector, a bootstrapping ensemble sampler, and a centroid-based clustering algorithm from scratch.

  TikTokMachine Learning EngineerCoding & AlgorithmsOnline Assessment
• Implement streaming SRM detector with late eventsMedium

  This question evaluates proficiency in stateful stream processing, statistical anomaly detection for sample ratio mismatch, and scalable system design concerns such as deduplication, late/out-of-order event handling, real-time aggregation, chi-square testing with Yates correction, bot-rate mitigation, sharding, and replay validation.

  TikTokData ScientistCoding & AlgorithmsHR Screen
• Maximize Distinct Purchases Within Budget ConstraintsMedium

  This question evaluates understanding of selection and optimization under budget constraints, algorithmic efficiency, and the ability to implement correct logic for maximizing the number of distinct items purchased.

  TikTokData ScientistCoding & AlgorithmsOnline Assessment
• Maximize min+max of contiguous subarrayMedium

  This question evaluates understanding of array algorithms and competency in identifying and reasoning about minimum and maximum values within contiguous subarrays, emphasizing extremal value handling.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Maximize products bought under budgetMedium

  This question evaluates algorithmic problem-solving skills including sorting, prefix-sum accumulation, binary search, greedy selection, careful tie-breaking for lexicographic order, and complexity analysis.

  TikTokData ScientistCoding & AlgorithmsOnline Assessment
• Optimize Station Sequence for Maximum Car Output in SimulationMedium

  This question evaluates a candidate's skills in scheduling and throughput optimization, including queue management and simulation-based performance analysis within constrained buffering and station sequencing.

  TikTokData ScientistCoding & AlgorithmsOnsite
• Parse a nested list from a stringMedium

  This problem tests your ability to parse recursive nested structures using stack-based iteration or recursion and string manipulation.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Parse chemical formula with multipliersMedium

  Parse chemical formula with multipliers evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Process LRU Cache OperationsMedium

  Implement an LRU cache through a deterministic stream of put and get operations, including updates, misses, and eviction order. The prompt defines an exact portable function contract and examples suitable for a later four-language console handoff.

  TikTokBackend Software EngineerCoding & AlgorithmsOnsite
• Reconstruct a tree from two traversalsMedium

  Reconstruct a tree from two traversals evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Remove the Fewest Overlapping IntervalsHard

  Tests greedy interval scheduling and sorting techniques to find the minimum number of intervals to remove so that no remaining intervals overlap.

  TikTokSoftware EngineerCoding & AlgorithmsOnsite
• Restore Every Valid IP AddressMedium

  Implement a backtracking algorithm to partition a digit string into four valid IPv4 octets, adhering to numerical range and leading-zero constraints.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Schedule Seller Tasks with Tier-Weighted Round RobinHard

  Design a task scheduler that dispenses seller tasks using tier-weighted round-robin across sellers while strictly preserving per-seller priority and FIFO order.

  TikTokSoftware EngineerCoding & AlgorithmsOnsite
• Solve array and tree algorithm challengesMedium

  This question evaluates algorithmic problem-solving skills across array, heap, and tree data structures, testing competencies in duplicate handling, frequency aggregation, and balancing root-to-leaf path sums within the Coding & Algorithms domain.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen
• Solve common string/DP/stack problemsMedium

  This problem tests your ability to identify and implement an efficient solution for finding the longest substring that satisfies specific constraints, requiring a sliding window approach.

  TikTokSoftware EngineerCoding & AlgorithmsTechnical Screen