Coding questions

1,899 resources · Page 21 of 80

1. Coding questions · TikTok

   Count islands using BFS without modifying grid

   This question evaluates understanding of BFS-based graph traversal on grids, managing visited state without modifying the input, and techniques for encoding island shapes to detect distinct configurations.

2. Coding questions · Snapchat

   Count islands with eight-direction adjacency

   This question evaluates a candidate's competency in graph traversal algorithms and data-structure trade-offs by counting connected components on a grid with eight-direction adjacency, focusing on BFS/DFS behavior and optional Union-Find approaches.

3. Coding questions · Microsoft

   Count k for consecutive-sum generator

   This question evaluates number-theoretic reasoning and understanding of arithmetic progressions, focusing on how sums of consecutive positive integers can be characterized and counted.

4. Coding questions · Pinduoduo

   Count Longest Substrings After Character Replacements

   Count the longest substring occurrences that can become one repeated uppercase letter within a replacement budget, counting positions rather than replacement choices.

5. Coding questions · Microsoft

   Count Non-Decreasing Arrays with Prescribed Digit Sums

   Count non-decreasing arrays whose values are at most 5000 and match specified decimal digit sums, returning the total modulo 1000000007.

6. Coding questions · Optiver

   Count nonnegative buy/sell sequences

   This question evaluates combinatorial reasoning and algorithmic analysis by asking for the count of constrained buy/sell sequences, testing competence in counting under constraints and reasoning about sequence invariants.

7. Coding questions · Squarespace

   Count Numbers Inside All Intervals

   This question evaluates the ability to compute intersections of numeric intervals and perform efficient counting over an array, testing competencies in range handling, multiplicity accounting, and time-complexity-aware algorithm design.

8. Coding questions · ByteDance

   Count Numbers with an Even Number of Digits

   Count how many positive integers in an array have an even number of decimal digits. Respect ordinary representations without leading zeroes, count repeated values independently, and handle boundaries such as 10 and 10000 correctly.

9. Coding questions · Optiver

   Count OPTIVER in a Letter Grid Across Rows, Columns and Reversed Readings

   Count how many times the word OPTIVER appears in a rectangular grid of uppercase letters, reading rows left to right or right to left and columns top to bottom or bottom to top. Tests careful grid traversal, direction handling, boundary checks and precise counting rules.

10. Coding questions · Capital One

    Count ordered pairs that concatenate to target

    This question evaluates a candidate's ability to manipulate string and numeric representations, perform efficient counting, and leverage associative data structures to identify matching concatenations.

11. Coding questions · Capital One

    Count Pairs of Numbers That Become Equal After at Most One Digit Swap

    Given a list of integers, count the index pairs whose values are equal or become equal after swapping two digits inside one of the two numbers, where leading zeros created by a swap are dropped. It tests digit manipulation, careful handling of numbers with different lengths, and hashing to avoid comparing every pair.

12. Coding questions · Meta

    Count palindrome substrings in a string

    This question evaluates proficiency in string algorithms, algorithmic design, and complexity analysis by targeting palindromic substring counting, string manipulation, and conceptual linear-time techniques.

13. Coding questions · Amazon

    Count partitions and equal-cost packages

    This question evaluates string-processing and combinatorial counting skills, including tracking distinct-character occurrences across contiguous partitions and using frequency-based pairing logic on arrays to form equal-cost packages.

14. Coding questions · Uber

    Count paths with prime-ending jumps

    This question evaluates a candidate's ability to design and implement dynamic programming for counting paths, combining combinatorial reasoning with modular arithmetic and handling step-size constraints tied to primes ending in digit 3.

15. Coding questions · Turing

    Count permutations with exactly n inversions

    This Coding & Algorithms question evaluates combinatorial counting and algorithmic skills related to permutations and inversion counts, emphasizing dynamic programming and modular arithmetic for large-result handling.

16. Coding questions · Amazon

    Count regions with DFS

    This question evaluates proficiency in graph traversal and grid-based connected-component detection using depth-first search on a binary m x n grid, along with algorithmic complexity analysis and techniques to avoid revisiting cells.

17. Coding questions · OneMain Financial

    Count, Return, Find, and Select in SQL Queries

    This question evaluates proficiency in SQL data manipulation, specifically aggregation, grouping, filtering, and identification of extrema within a single-table orders dataset.

18. Coding questions · ByteDance

    Count Same-Day Registered Posters

    This question evaluates SQL querying skills, including joining relational tables, date handling, aggregation, and deduplicating users across events. Commonly asked in Coding & Algorithms interviews for data scientists, it assesses practical relational database querying and analytics tasks—filtering, grouping, and counting distinct users across tables—and tests practical application of SQL rather than purely conceptual database theory; this summary is in English.

19. Coding questions · ByteDance

    Count Similar Photo Groups

    This question evaluates understanding of graph connectivity and equivalence relations, requiring recognition of connected components from an adjacency-matrix representation of pairwise similarity.

20. Coding questions · ByteDance

    Count Special Subarrays by Modular Frequency

    This question evaluates the ability to apply modular arithmetic, frequency tracking, and prefix-count reasoning to efficiently count subarrays that satisfy a congruence condition, testing algorithmic problem-solving and scalable complexity management.

21. Coding questions · Reevo

    Count sports by calendar quarter in SQL

    This question evaluates a candidate's ability to perform date-based grouping and aggregation in SQL, including extracting year and calendar quarter and counting rows per sport.

22. Coding questions · Waymo

    Count Squares Formed by Intersections of Vertical and Horizontal Segments

    Given vertical and horizontal line segments defined by start and end points, count the axis-aligned squares whose four corners are all segment intersection points. Tests intersection detection, square enumeration, and faster ways to find which segments cross each other.

23. Coding questions · Optiver

    Count Straight-Line Occurrences of a Word in a Letter Grid, Rows and Columns Only

    Count how many times a target word appears in a grid of letters when read in a straight line along a row or down a column, with no turns and overlapping matches counted separately. It tests careful grid traversal, boundary handling, precise occurrence counting rules and efficient string matching.

24. Coding questions · Capital One

    Count Subarrays Containing at Least k Disjoint Pairs of Equal Values

    Count the contiguous segments of an integer array, framed as fruit types on a conveyor belt, that contain at least k pairs of equal values with no position used in two pairs. Tests reasoning about how the number of disjoint pairs changes as a segment grows, and efficient counting on inputs of up to 100,000 elements.