Topic
Coding & Algorithms interview questions
3276 Coding & Algorithms questions from 366 companies, with hints, runnable code and solution walkthroughs.
273 easy2539 medium464 hard
Coding & Algorithms interview questions by the numbers
Last updated
Katkat has 3,276 Coding & Algorithms interview questions from 366 companies; the most come from Amazon (7%), Meta (7%) and Google (6%). By difficulty: 8% easy, 78% medium and 14% hard. The most common round is Technical Screen (52%). Frequent concepts include Algorithms, Data Structures, Arrays and Greedy.
Companies (366)
Difficulty
- Easy8% · 273
- Medium78% · 2539
- Hard14% · 464
Interview rounds
- Technical Screen52% · 1706
- Onsite33% · 1080
- Online Assessment13% · 427
- HR Screen1% · 37
- Other1% · 26
Roles
- Software Engineer80% · 2629
- Machine Learning Engineer8% · 253
- Data Scientist7% · 241
- Data Engineer1% · 45
- Backend Engineer1% · 26
Frequent concepts
- Algorithms9% · 302
- Data Structures7% · 228
- Arrays5% · 176
- Greedy5% · 164
- Optimization5% · 151
- Hash Map4% · 124
Most mentioned in interview experiences
- 1.Solve Algorithmic Challenges in Online Coding Assessments15 reports
- 2.Solve LeetCode string and list problems11 reports
- 3.Solve sliding-window and heap problems8 reports
- 4.Implement LRU cache with O(1) ops7 reports
- 5.Implement and Analyze an LRU Query Cache6 reports
- 6.Determine Length of Longest Unique Substring5 reports
- 7.Match-3 Grid: Find Horizontal and Vertical Runs, Then Clear and Drop Cells5 reports
- 8.Design a single- and multi-threaded web crawler4 reports
- 9.Find an Exit in a URL Maze4 reports
- 10.Find deployable slots in a recurring week from allowed and freeze windows4 reports
Counted from 781 candidate interview experiences on Katkat. How we collect and count
Showing 1111–1140 of 3276 results
This problem tests recursive tree evaluation logic and the ability to optimize updates by propagating changes only to necessary ancestors.
GoogleSoftware EngineerCoding & AlgorithmsOnsiteTests implementation of a Trie (prefix tree) data structure to support word insertion, exact word search, prefix existence checks, and lexicographical autocomplete suggestions with a capacity limit.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to process sequential text data, efficiently store word adjacency frequencies, and retrieve the most likely successor.
GoogleSoftware EngineerCoding & AlgorithmsOnsiteThis problem tests your ability to design a memory-efficient data structure for storing n-gram probabilities and performing fast lookups for the most likely next word.
GoogleData ScientistCoding & AlgorithmsOnline AssessmentThis problem tests your ability to manage state and apply custom sorting logic to simulate resource allocation across time intervals.
GoogleSoftware EngineerCoding & AlgorithmsOnsiteTests tracking vehicle state across interleaved chronological event streams and computing distance-based segment tolls regardless of travel direction or checkpoint repetition.
GoogleSoftware EngineerCoding & AlgorithmsOnsiteThis problem tests your ability to determine if one board state can be transformed into another using reversible movement rules, requiring the identification of invariants to avoid exhaustive searching.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenDetermine if a non-negative integer has digits that are monotonically non-decreasing from left to right, handling edge cases without unnecessary memory allocation.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenDetermine whether a proposed half-open interval overlaps with any interval in an unsorted list. This tests basic interval overlap logic and boundary condition handling.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates string-processing skills and combinatorial reasoning about character multisets, specifically anagram recognition, substring enumeration, and the use of efficient representations for repeated checks.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates string-processing skills such as substring enumeration and membership testing against a dictionary, along with algorithmic reasoning about correctness and complexity.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenChoose a set of jobs, each with a start time, end time and profit, so that no two chosen jobs overlap and the total profit is as large as possible. It tests sorting intervals, defining an optimal-substructure recurrence, and finding the latest compatible earlier job efficiently for large inputs.
GoogleSoftware EngineerCoding & AlgorithmsOnsiteDetermine at most one obstacle to remove in a grid to minimize the maximum time for signals to reach all target cells from multiple sources.
GoogleSoftware EngineerCoding & AlgorithmsOnsiteThis problem tests your ability to model uncertainty and implement a greedy strategy to minimize the expected search space size when provided with restricted (green-only) feedback.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to manage state in a queue-based simulation and implement complex tie-breaking logic using data structures like heaps or prioritized queues.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenImplement and compare recursive and iterative traversals to compute the depth-weighted sum of an arbitrarily nested list of integers, handling deep nesting and edge cases.
GoogleSoftware EngineerCoding & AlgorithmsOnsiteThis problem tests your ability to efficiently compute shortest path distances from multiple sources to all reachable grid cells using multi-source Breadth-First Search (BFS).
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates combinatorial optimization, state-space reasoning, and algorithmic design for constrained token movements on a linear board, and falls under the Coding & Algorithms domain.
GoogleSoftware EngineerCoding & AlgorithmsOnline AssessmentThis question tests the ability to solve pathfinding problems using non-standard cost metrics: first, finding a minimax path in a grid, and second, calculating the earliest arrival time in a network with weighted edges.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to manage overlapping intervals in a circular domain by converting cyclic tasks into linear sub-intervals and applying a sweep-line or greedy approach to determine resource requirements.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates a data scientist's competency in model evaluation for imbalanced binary classification, covering understanding of precision–recall dynamics, calibration, AUPRC, cost‑sensitive metrics, and practical implementation concerns like computing thresholds and handling ties and numerical edge cases; domain: Coding & Algorithms and machine learning model evaluation. It is commonly asked in technical interviews because it assesses both conceptual understanding of evaluation trade‑offs and the practical application of efficient, robust metric computation and threshold selection under asymmetric costs and operational constraints.
GoogleData ScientistCoding & AlgorithmsTechnical ScreenThis question evaluates understanding of interval-based resource allocation and job grouping by identifier, testing competency in managing overlapping time intervals, capacity planning, and handling day-boundary truncation.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates understanding of graph traversal and shortest-path techniques under constraints, including avoidance of forbidden nodes, multi-criteria optimization (minimizing dangerous-node visits then steps), and reasoning about augmented state and visited-structure design.
GoogleSoftware EngineerCoding & AlgorithmsOnsiteThis question evaluates proficiency with graph algorithms, shortest-path and reachability concepts when nodes are removed or blocked, and the ability to analyze time and space complexity across directed and undirected graphs.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to maintain order statistics in a sliding window using balanced data structures or heaps to perform efficient removals and updates while excluding the top k elements.
GoogleSoftware EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to identify contiguous subarrays that follow an arithmetic progression with a common difference of 1 (consecutive steps) and calculate the sum of elements within these subarrays efficiently.
GoogleMachine Learning EngineerCoding & AlgorithmsOnsiteMerge two sorted lists of disjoint closed intervals into a single sorted list of disjoint intervals in linear time.
GoogleSoftware EngineerCoding & AlgorithmsOnsiteConsolidate overlapping on-call shift intervals into non-overlapping segments, each annotated with the sorted list of active engineers.
GoogleSoftware EngineerCoding & AlgorithmsOnline AssessmentThis problem tests your ability to design a constructive grid layout that satisfies connectivity and size constraints, followed by pathfinding through dynamic or constrained environments.
GoogleMachine Learning EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to model geometric data as a graph and identify connected components using traversal algorithms or Disjoint Set Union (DSU).
GoogleSoftware EngineerCoding & AlgorithmsTechnical Screen