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Coding & Algorithms Interview Questions
Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.
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Showing 2311–2340 of 3276 results
- PinterestMediumData ScientistFind list pair with maximum overlap
This question evaluates proficiency with set operations and similarity metrics (Jaccard), scalable algorithm design and complexity analysis for large datasets, and the ability to handle streaming updates and deterministic tie-breaking.
Coding & AlgorithmsOnsite - PinterestMediumSoftware EngineerFind minimum shuttle transfers
Find minimum shuttle transfers 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.
Coding & AlgorithmsOnline Assessment - PinterestMediumSoftware EngineerFind the Minimum Number of Coins for an Amount
Tests dynamic programming and breadth-first search techniques to find the minimum number of coin denominations required to reach a target value, including edge cases like zero and unreachable sums.
Coding & AlgorithmsOnsitedynamic-programmingbfsarrays - PinterestMediumMachine Learning EngineerFirst Word Matching Each Prefix Query
This problem tests your ability to efficiently query a list of strings to find the first occurrence that matches a given prefix, focusing on optimal space-time tradeoffs using tree-based or map-based indexing.
Coding & AlgorithmsOnsiteTrieHash MapString Processing - PinterestMediumMachine Learning EngineerGenerate all hyperparameter combinations
This problem tests your ability to generate the Cartesian product of multiple lists, a fundamental task in grid search for hyperparameter tuning.
Coding & AlgorithmsTechnical ScreenCombinatoricsRecursionIteration - PinterestMediumMachine Learning EngineerHierarchical Access Control for an Advertising Platform
This problem tests graph traversal algorithms and efficient membership checking within a directed acyclic graph (DAG) representing hierarchical organizational permissions.
Coding & AlgorithmsOnsiteGraphsDAGBFS/DFS - PinterestMediumData ScientistHow to Design a Proportional Randomized Sampler?
This question evaluates proficiency in randomized algorithms and probabilistic sampling, with emphasis on numerical precision, large-weight handling, and memory-versus-accuracy trade-offs. Commonly asked in Coding & Algorithms interviews for data-science roles, it assesses practical application ability grounded in conceptual understanding of numerical stability and relevant data-structure choices.
Coding & AlgorithmsOnsite - PinterestMediumData ScientistImplement Data Structure for Top-K Elements in Streams
This question evaluates competency in streaming algorithms, dynamic data structures for maintaining top-K elements in real time, and scalability considerations for handling large or distributed input streams.
Coding & AlgorithmsOnsite - PinterestMediumData ScientistImplement Function to Return First n Prime Numbers
This question evaluates algorithmic problem-solving and basic number-theory competency by requiring generation of prime numbers with attention to correctness and performance characteristics.
Coding & AlgorithmsOnsite - PinterestMediumData ScientistImplement Jackknife and Random Choice
Implement weighted random selection from scratch and compute delete-1 jackknife estimates of parameter bias and standard error for an arbitrary statistical estimator.
Coding & AlgorithmsTechnical Screensamplingresamplingstatistics - PinterestMediumData ScientistImplement LRUCache with O(1) Operations and Thread Safety
This question evaluates a candidate's ability to implement a constant-time LRU cache and reason about thread-safety and concurrent access, testing data structure design and concurrency competencies in the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - PinterestMediumMachine Learning EngineerImplement a Sparse Matrix Class
Design and implement a memory-efficient sparse matrix class supporting entry retrieval, updates, addition, and matrix multiplication.
Coding & AlgorithmsTechnical Screensparse-matrixhash-tablelinear-algebra - PinterestHardMachine Learning EngineerImplement a Stateful Search Autocomplete Session
Design an interactive autocomplete system that tracks query frequencies, returns the top 3 ranking prefix matches per keystroke, and commits completed queries to dynamic history.
Coding & AlgorithmsTechnical ScreenTrieHash TableDesign - PinterestMediumSoftware EngineerImplement a min-heap column allocator
This question evaluates a candidate's competency in data structures (priority queues/min-heaps), online algorithm design for stream processing, and complexity and memory analysis.
Coding & AlgorithmsTechnical Screen - PinterestMediumData ScientistImplement and extend My Calendar III
This question evaluates competency in designing and implementing efficient dynamic interval data structures, handling correctness for duplicate and nested intervals, extending APIs with cancellation and point queries, and performing rigorous worst-case time/space analysis and resource-adaptation.
Coding & AlgorithmsTechnical Screen - PinterestEasyData ScientistImplement np.random.choice
This problem tests your ability to implement weighted random sampling from an array, focusing on probability distribution handling and efficient selection algorithms.
Coding & AlgorithmsTechnical ScreenProbabilitySamplingAlgorithms - PinterestMediumSoftware EngineerImplement sparse matrix storage, addition, and multiplication
This problem tests your ability to design a memory-efficient representation for sparse matrices and implement arithmetic operations while leveraging the sparsity of the data.
Coding & AlgorithmsOnsiteArraysHash MapsLinear Algebra - PinterestMediumSoftware EngineerImplement stream line reader and settle balances
This question evaluates streaming I/O and buffered string-processing competency for Part 1 and transaction netting with balance computation for Part 2, covering skills in memory-bounded parsing, data-structure bookkeeping, and algorithmic flow reasoning.
Coding & AlgorithmsOnsite - PinterestMediumSoftware EngineerImplement string-based big integer multiplication
Implement multiplyStrings(a, b) to multiply two non-negative integers given as decimal strings, returning the product as a string without any big-integer or arbitrary-precision library. The solution covers grade-school O(n*m) long multiplication with linear memory, the Karatsuba and FFT/NTT scaling alternatives, correct carry and leading/trailing-zero handling, and a full edge-case test plan.
Coding & AlgorithmsOnsite - PinterestEasyMachine Learning EngineerImplement string-based rounding without floats
This question evaluates proficiency in string-based numeric processing, arbitrary-precision arithmetic concepts, precise rounding rules including deterministic tie-breaking, and handling of sign and decimal edge cases, and falls under the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - PinterestHardMachine Learning EngineerImplement trie-based autocomplete
This problem tests your ability to implement a space-efficient Trie data structure capable of storing strings along with associated weights to return top-k suggestions for a given prefix.
Coding & AlgorithmsOnsiteTrieData StructuresStrings - PinterestMediumData ScientistImplement weighted random choice
This problem tests your ability to implement efficient weighted random selection, specifically focusing on cumulative distribution functions and binary search to achieve optimal query performance.
Coding & AlgorithmsTechnical ScreenAlgorithmsProbabilityBinary Search - PinterestMediumSoftware EngineerInsert Operators to Reach a Target
Tests backtracking with operator precedence handling and operand formatting to construct all valid arithmetic expressions evaluating to a target value.
Coding & AlgorithmsOnsitebacktrackingrecursionstring - PinterestHardSoftware EngineerList All Plus/Times Expressions Reaching a Target Under Operator Precedence
Tests backtracking and state tracking with operator precedence to evaluate and enumerate arithmetic expressions using addition and multiplication.
Coding & AlgorithmsOnsiteBacktrackingRecursionMath - PinterestMediumSoftware EngineerList Unallocated Experiment Buckets
Determine all unassigned experiment bucket IDs in the range [0, total_buckets - 1] given lists of control and treatment bucket allocations.
Coding & AlgorithmsTechnical Screenarrayhash-tablebit-manipulation - PinterestMediumSoftware EngineerMark and Compact a Heap-Indexed Subtree
This problem tests array manipulation, heap-based tree traversal, and stable partitioning techniques while requiring memory efficiency without modifying the original input.
Coding & AlgorithmsOnline AssessmentArraysTreesHeap - PinterestMediumData ScientistMaximize Non-Overlapping Task Scheduling Efficiency
This question evaluates understanding of interval scheduling and resource optimization, focusing on reasoning about time intervals and conflict-free selection of tasks.
Coding & AlgorithmsOnsite - PinterestMediumSoftware EngineerMinimum Transfers Between Pin Boards
Tests breadth-first search and graph modeling skills by finding the shortest path across overlapping collections without constructing a dense graph between every pair.
Coding & AlgorithmsOnsiteBFSGraphHash Map - PinterestMediumSoftware EngineerRebalance Experiment Buckets with Minimal Reassignment
Implement a deterministic rebalancing algorithm that redistributes entities among experiment buckets to meet exact target counts while minimizing reassignments and applying canonical tie-breaking.
Coding & AlgorithmsTechnical Screengreedysortinghash-map - PinterestMediumSoftware EngineerReconstruct an Itinerary from Flight Tickets
Tests graph modeling, depth-first search (DFS), and Hierholzer's algorithm to construct an Eulerian path with lexicographical tie-breaking.
Coding & AlgorithmsOnsiteGraphDFSEulerian Path
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