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 3091–3120 of 3276 results
This question evaluates understanding of graph modeling and traversal techniques, particularly transitive closure, cycle detection, and BFS-based permission propagation across nested group relationships.
VerkadaSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates understanding of cache eviction policies and data structure design, focusing on LRU and LFU semantics and the ability to support O(1) average-time get/put operations.
VerkadaSoftware EngineerCoding & AlgorithmsOnsiteThis question evaluates proficiency in string processing, frequency counting, and edge-case handling by requiring implementation of Wordle-like feedback scoring for guess versus secret words.
VerkadaSoftware EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to combine a Least Recently Used (LRU) cache mechanism with a dynamic programming approach for optimization.
VerkadaFrontend EngineerCoding & AlgorithmsOnsiteFind maximal motion periods for one camera or the simultaneous intersection across many piecewise-constant camera streams. The prompt defines exact integer timestamps, threshold scaling, last-reading horizon, undefined prefixes, inclusive endpoints, and deterministic interval ordering for portable console verification.
VerkadaSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates array manipulation and in-place merging skills, specifically understanding sorted sequences, pointer/index management, and space-time trade-offs within array algorithms, and it falls under the Coding & Algorithms domain.
VerkadaSoftware EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to validate a 9x9 grid against Sudoku-like constraints using efficient lookups and index arithmetic.
VerkadaSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates the ability to design and implement game-state logic for a Connect Four-style board, covering board data structures, coordinate and boundary handling, gravity-based token placement, and efficient pattern detection for consecutive tokens in the Coding & Algorithms domain.
Virtu FinancialData ScientistCoding & AlgorithmsTechnical ScreenThis problem tests your ability to determine an optimal ordering strategy and apply dynamic programming to maximize a cumulative score subject to specific operations.
Virtu FinancialData ScientistCoding & AlgorithmsTechnical ScreenDetermine the maximum number of edges an undirected, simple graph on n vertices can have without containing any triangle (K3), and construct one such extremal graph.
Virtu FinancialQuantitative ResearcherCoding & AlgorithmsOnsiteEach plot in a row has a maximum allowed tower height. Choose tower heights that rise to a single peak and then fall, never exceeding any cap, so that the total height is as large as possible. Tests reasoning about the peak position, per-position caps, and 64-bit sums.
Virtu FinancialQuantitative ResearcherCoding & AlgorithmsOnline AssessmentGiven a list of past loans between people, compute the minimum number of new money transfers needed so that everyone's net balance returns to zero. Tests reducing a transaction log to net balances and searching for the fewest settling transfers under small input bounds.
Virtu FinancialQuantitative ResearcherCoding & AlgorithmsOnline AssessmentStarting from a pair of positive integers, each move adds one coordinate to the other. Decide whether an exact target pair can be reached. Tests reasoning about reachability when values go up to one billion and simulating every forward move is far too slow.
Virtu FinancialQuantitative ResearcherCoding & AlgorithmsOnline AssessmentDetermine the maximum number of contiguous, non-empty subarrays an array can be partitioned into such that each subarray has the same sum.
Virtu FinancialSoftware EngineerCoding & AlgorithmsOnline AssessmentThis question evaluates algorithmic problem-solving skills in combinatorics and resource-constrained subset-sum computation, focusing on dynamic programming, optimization, and complexity analysis within the Coding & Algorithms domain.
VisaSoftware EngineerCoding & AlgorithmsTechnical ScreenDetermine the number of connected components in an undirected graph represented by an adjacency matrix, accounting for transitive relationships.
VisaSoftware EngineerCoding & AlgorithmsOnline AssessmentTests linear-time frequency-map counting across two independent arrays to find pairs that sum to a target, properly accounting for duplicates and 64-bit integer overflow.
VisaSoftware Engineer ICoding & AlgorithmsOnline AssessmentThis problem tests graph traversal techniques on a 2D grid, focusing on identifying connected components without modifying the original input or exceeding recursion limits.
VisaSoftware Engineer ICoding & AlgorithmsOnline AssessmentA string-processing coding problem: split a sentence on spaces and count the tokens that contain only English letters and the punctuation marks comma, period, question mark and exclamation mark. It tests careful tokenization with repeated spaces and exact character-class rules.
VisaSoftware EngineerCoding & AlgorithmsOnline AssessmentThis problem tests dynamic programming skills, specifically the ability to count subsequences that satisfy a positional movement constraint based on element parity.
VisaSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates algorithmic skills in designing efficient dynamic data structures and performing event-driven simulation with mutable state, specifically managing cyclic capacity resets and permanent closures in the Coding & Algorithms domain.
VisaSoftware EngineerCoding & AlgorithmsOnsiteA scheduling coding problem: given everyone's busy intervals as text entries with inclusive minute times, find the earliest start for a meeting of k minutes after the day's first busy minute, or report that none exists. It tests time parsing, merging overlapping intervals and off-by-one boundaries.
VisaSoftware EngineerCoding & AlgorithmsOnline AssessmentPractice locating a target value in a strictly increasing array of distinct integers, returning its zero-based index or -1 when it is absent. The task checks logarithmic-time search over sorted data, precise loop boundaries, and correct handling of single-element arrays and values that fall between or outside the stored elements.
VisaSoftware EngineerCoding & AlgorithmsOnsiteThis problem tests the ability to optimize for the bottleneck edge in a path rather than the total path cost, typically solvable using a modified Dijkstra's algorithm or a Union-Find approach.
VisaSoftware EngineerCoding & AlgorithmsOnline AssessmentThis problem tests the implementation of Dijkstra's algorithm using a priority queue to find the shortest path in a weighted undirected graph.
VisaSoftware Engineer ICoding & AlgorithmsOnline AssessmentA grid coding problem: find the length of the longest walk of strictly increasing values in an integer matrix, moving only up, down, left or right. It tests modeling a grid as a graph, handling equal neighboring values correctly, and an efficient search over grids of up to 40,000 cells.
VisaSoftware EngineerCoding & AlgorithmsOnsiteThis question evaluates the ability to design dynamic data structures and perform algorithmic complexity analysis for maintaining pair-sum counts under element replacements, testing skills in efficient query/update handling and scalability.
VisaSoftware EngineerCoding & AlgorithmsOnsiteAn array optimization problem: maximize the sum of each element times its index when any two elements may be swapped but every element can take part in at most one swap. It tests modeling the at-most-once rule precisely and finding the best set of disjoint swaps within small input limits.
VisaSoftware EngineerCoding & AlgorithmsOnline AssessmentGiven a digit string and a list of digit targets, return for each target the length of the shortest prefix whose characters could build every permutation of that target, or -1 if no prefix can. It tests character frequency counting, precomputation over a string, and answering many queries efficiently.
VisaSoftware EngineerCoding & AlgorithmsOnline AssessmentThis multi-part question evaluates algorithmic problem-solving skills in array manipulation, optimization (maximizing capped contributions), modular combinatorics (counting divisible-sum triplets), and sequence selection/dynamic decision-making for longest selectable non-decreasing subarrays.
VisaSoftware EngineerCoding & AlgorithmsOnline Assessment