hash-set Interview Questions
18 interview questions in our bank cover hash-set, most of them Coding & Leetcode-style Questions. They average 2.5/5 difficulty — medium — and each one was reported by a candidate after a real interview. Companies known to ask about hash-set: Amazon.
Practice these on the problems board →Companies that ask about hash-set
Question mix
- Coding & Leetcode-style Questions18
Difficulty
- 2/5 — easy11
- 3/5 — medium5
- 4/5 — hard2
Questions tagged hash-set
Volumes Purchased Each Day
3/5This reported Amazon interview question evaluates your ability to track sequential availability and conditional acquisition logic over daily data streams. You must determine which items can be successfully claimed on each day based on the prerequisite that all preceding sequential items are already in your possession. The challenge tests efficient state tracking and array manipulation under progressive constraints. Access the complete problem description and expert model solution by securing a paid subscription.
Coding & Leetcode-style QuestionsAmazonDiagonal Nearest-Unvisited Redirect Simulation
4/5Simulate a dynamic pathfinding process across a coordinate plane where servers are visited sequentially based on directional vectors and step multipliers. Reported as an advanced algorithmic question from Amazon interviews, this task challenges you to locate the closest unvisited node along specific diagonal trajectories and update your current position accurately while maintaining a strict history of visited locations. Crafting an efficient solution requires smart spatial indexing to avoid performance bottlenecks during ray-tracing steps. Unlock the complete problem details and the authoritative model solution with a subscription.
Coding & Leetcode-style QuestionsAmazonCount Matching D-Length Substrings
3/5This Amazon interview question challenges you to analyze two text sequences and quantify how many fixed-length segments from the first text can be found anywhere within the second text. It tests your string manipulation skills, sliding window patterns, and hashing strategies required to optimize substring comparisons. Developing an optimal solution involves avoiding redundant checks to maintain strong performance under tight time constraints. To review the complete problem details and clean code solution, a subscription is required.
Coding & Leetcode-style QuestionsAmazonUnique Common Elements of Two Lists
2/5This common coding interview question, frequently asked at Amazon, asks developers to find the distinct shared items between two collections while preserving the precise ordering established in the second input. The challenge evaluates your understanding of hash sets, linear time complexities, and sequence preservation techniques in Python. It is an excellent test of fundamental data structure manipulation skills. Unlock the full prompt and efficient code implementation by upgrading to a paid subscription.
Coding & Leetcode-style QuestionsAmazonCount Unique Morse Code Translations
2/5This interview question, frequently reported at Amazon, challenges candidates to process a collection of text strings and determine how many unique representations they produce when converted into dot-dash sequences. The exercise evaluates your ability to use hash-based data structures to filter duplicates efficiently while manipulating string collections. It tests fundamental parsing and set operations in a straightforward algorithmic scenario. Access to the comprehensive problem description and optimal algorithmic solution requires a subscription.
Coding & Leetcode-style QuestionsAmazonLongest Squaring Chain of Rice Bags
3/5Encountered frequently in technical interviews at Amazon, this challenge tests your skill in identifying specialized numerical relationships within collections of data. You are tasked with discovering the largest subset of values where each consecutive element is the square of the preceding one, returning the total count or indicating if no valid sequence exists. Unlocking the full problem description, edge cases, and the complete model solution requires an active paid subscription.
Coding & Leetcode-style QuestionsAmazonMinimum Front Removals for a Distinct Suffix
2/5This interview challenge, frequently reported during Amazon hiring loops, asks candidates to determine the fewest elements that must be discarded from the beginning of a sequence so that every remaining item is completely unique. The problem evaluates your ability to manage subarray boundaries efficiently and optimize frequency tracking under constraints. To explore the complete problem statement, optimal algorithmic strategy, and fully written code solutions, an active subscription is required.
Coding & Leetcode-style QuestionsAmazonOperations to Zero the Array
2/5Investigate a reduction puzzle reported from Amazon interviews that challenges you to eliminate all positive integers in an array through iterative subtraction based on the current minimum value. The goal is to compute the absolute minimum steps required to clear the dataset entirely. This scenario tests your understanding of array traversal, simulation efficiency, and mathematical reductions. Unlock the full problem specifications and the optimal code solution with a subscription.
Coding & Leetcode-style QuestionsAmazonCount Unique Strings After One Reversal
3/5In this intriguing string-manipulation problem reported by Amazon, you must determine how many distinct words can be generated by reversing a single continuous segment within a given text. The exercise tests your string processing skills, hashing techniques, and ability to handle overlapping palindromic patterns efficiently. You will need to carefully analyze substring boundaries to avoid overcounting duplicate configurations. Reviewing the full problem description and the optimized reference solution requires a paid subscription.
Coding & Leetcode-style QuestionsAmazonLongest Distinct-Character Bracket Prototype
2/5This reported Amazon interview question challenges you to process a collection of text strings and extract a specialized signature based on unique letters. You will need to evaluate character variety while implementing custom tie-breaking logic to select the most optimal pattern. The challenge assesses your string manipulation skills, frequency tracking, and sorting efficiency. Access to the full problem description, edge cases, and complete optimal solution requires an active subscription.
Coding & Leetcode-style QuestionsAmazonDistinct Averages of High-Low Pairs
2/5In this engaging interview problem reported at Amazon, you are tasked with repeatedly combining extreme values from a dataset and computing their averages until no elements remain. The main objective is to determine how many unique mean values are produced throughout this iterative reduction process. This exercise evaluates your proficiency with sorting techniques, two-pointer methods, and hash-based collections to track distinct outcomes efficiently. Access to the full problem statement, test cases, and a comprehensive code solution requires a paid subscription.
Coding & Leetcode-style QuestionsAmazonFriend Purchase Recommendations
2/5This Amazon interview exercise requires you to cross-reference personal shopping history with social network purchases to generate curated item suggestions. It evaluates your skill in handling relational data sets, filtering unique exclusions, and sorting results alphabetically. Unlock the full problem details and reference solution by subscribing today.
Coding & Leetcode-style QuestionsAmazonMedian of Subarray Uniqueness
3/5Sourced from Amazon interview rounds, this algorithmic puzzle requires you to calculate the uniqueness metric for every contiguous subarray within a given sequence and find the median of those collected values. You must efficiently manage distinct element counts across multiple overlapping windows to avoid performance bottlenecks on large inputs. This task tests your mastery of advanced array manipulation and frequency tracking strategies. Get full access to the problem statement and optimized solution code with our paid subscription.
Coding & Leetcode-style QuestionsAmazonMinimum Redundancy-Free Segments
2/5In this Amazon interview question, you are tasked with analyzing a given string to determine the fewest possible contiguous sections it can be divided into. Each of these sections must adhere to a specific rule: all characters within it must be unique. This problem evaluates your ability to segment data efficiently while satisfying a distinctness constraint, often involving greedy strategies or character tracking. The full problem and model solution require a subscription.
Coding & Leetcode-style QuestionsAmazonDetect Duplicate Within a Sliding Window
2/5This Amazon interview question asks you to examine a continuous stream of identifiers to spot any repeating values occurring within a fixed sliding distance. The problem evaluates your ability to maintain rolling data structures, such as hash sets or frequency maps, to efficiently check membership constraints over moving subranges. Developing an optimal linear-time approach is crucial for handling large data streams. Access the complete problem description and model solution with a subscription.
Coding & Leetcode-style QuestionsAmazonData Locations After Moves
2/5Examine a position-tracking simulation puzzle highlighted in Amazon interview rounds. This task involves updating and maintaining element coordinates through a sequence of relocation steps while correctly tracking the final occupied slots in sorted order. It assesses your ability to efficiently manage collections and manipulate tracking maps under dynamic changes. Discover the complete problem guidelines and clean architectural solution by subscribing today.
Coding & Leetcode-style QuestionsAmazonMinimum Insertions So No Subarray Sums to Zero
4/5This challenging Amazon interview question requires determining the smallest number of strategic insertions needed within an integer sequence to guarantee that no continuous subset adds up to zero. Candidates must apply advanced array manipulation and algorithmic optimization techniques to efficiently handle cumulative sums and boundary constraints. This problem evaluates your ability to recognize hidden numeric patterns and maintain state efficiently. Unlock the full problem breakdown and expert model solution with a paid subscription.
Coding & Leetcode-style QuestionsAmazonRemove Anagram Duplicates
2/5In this engaging string manipulation challenge reported from Amazon interviews, you are tasked with processing a collection of words to filter out redundant items that share identical character frequencies with any preceding entry, followed by sorting the remainder. This problem tests your ability to utilize hash maps or canonical representations for detecting structural equivalence among text elements. Candidates will learn how to streamline collection cleaning operations effectively. Unlock the full problem details and complete model code by subscribing today.
Coding & Leetcode-style QuestionsAmazon
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hash-set interview FAQ
- How many hash-set interview questions are there?
- 18 reported questions, mostly Coding & Leetcode-style Questions.
- Which companies ask hash-set questions?
- Amazon (18).
- How hard are hash-set questions?
- They average 2.5 out of 5: 11 at 2/5, 5 at 3/5, 2 at 4/5.