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 2521–2550 of 3276 results
This question evaluates understanding of number representations (Non-Adjacent Form), bit-level optimization, and formal proof techniques for demonstrating minimal Hamming weight, together with algorithmic complexity analysis.
SalesforceSoftware EngineerCoding & AlgorithmsOnline AssessmentArray problem: the bits of an all-zero binary string are set one at a time in the order given by a permutation; count the steps after which exactly the first i bits are set. It tests careful reasoning about prefix conditions and handling large inputs efficiently.
SalesforceSoftware EngineerCoding & AlgorithmsOtherTests 1D dynamic programming combined with primality testing to count valid partitions of a digit string into prime segments modulo 10^9 + 7.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteLinked list problem: delete every node whose value occurs more than once in an unsorted singly linked list, removing all copies and keeping the remaining nodes in their original order. It tests frequency counting, list traversal and careful handling of removals, including at the head of the list.
SalesforceSoftware EngineerCoding & AlgorithmsOtherDetermine which single character type to delete from a string so that greedily partitioning the remaining characters into substrings with all-unique characters yields the minimum number of segments.
SalesforceSoftware EngineerCoding & AlgorithmsOnline AssessmentThis question evaluates a candidate's understanding of string manipulation, hashing and frequency-count techniques, algorithmic optimization, and time/space complexity analysis when grouping anagrams.
SalesforceSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates string manipulation and adjacency-constraint handling in the first task and sequence analysis with minimal-removal and subsequence reasoning in the second, targeting competencies such as local transformation logic, subsequence recognition, and optimization under input constraints.
SalesforceSoftware EngineerCoding & AlgorithmsOnline AssessmentTests your ability to traverse an unrooted, undirected tree to compute its diameter (longest simple path) in linear time and space.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteAn integer problem: reduce a positive n to zero with the fewest operations, where each operation adds or subtracts a power of two. It tests reasoning about binary representations, proving a strategy optimal, and working safely with integers larger than 32 bits.
SalesforceSoftware EngineerCoding & AlgorithmsOnline AssessmentA string problem: delete every occurrence of one chosen lowercase letter, then split what remains into the fewest contiguous pieces with no repeated letters. It tests reasoning about optimal partitions, evaluating every deletion choice efficiently, and edge cases on strings up to 200,000 characters.
SalesforceSoftware EngineerCoding & AlgorithmsOnline AssessmentFind a celebrity in a knows matrix with linear candidate elimination followed by complete verification that the candidate knows nobody and is known by everyone else.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteTests the ability to model workflow dependencies as a directed graph, perform topological sorting, and detect cycles.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteReturn the one-based kth smallest value from a potentially deep binary search tree represented by parallel value and child-index arrays. Handle empty trees and out-of-range values of k using the specified sentinel.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteFind the lowest common ancestor of two nodes in an acyclic forest represented only by parent pointers. Return the node itself for equal inputs and minus one when the nodes belong to different trees.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteImplement an iterative traversal to flatten nested dictionaries and lists into fully-qualified paths leading only to string leaf values, returned in deterministic sorted order.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteReturn every balanced string made of n opening and n closing parentheses, for n up to 8, sorted in ascending lexicographic order. It tests systematic generation of combinatorial strings under a validity constraint, with an exact canonical ordering of the output.
SalesforceSoftware EngineerCoding & AlgorithmsTechnical ScreenGenerate every generalized abbreviation of a lowercase word by replacing selected character runs with positive counts. Merge consecutive skipped characters correctly and return the complete result in lexicographic order.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteThis question evaluates proficiency in modular arithmetic, safe 64‑bit integer operations, and algorithmic techniques for overflow‑resistant modular multiplication and exponentiation.
SalesforceSoftware EngineerCoding & AlgorithmsTechnical ScreenTests your ability to implement a classic divide-and-conquer merge sort algorithm from scratch, maintaining stability and achieving O(n log n) time complexity without relying on built-in sorting utilities.
SalesforceMember of Technical StaffCoding & AlgorithmsOnsiteThis question evaluates front-end web development competencies, including DOM manipulation, CSS-driven UI state, JavaScript timing and asynchronous state management for interactive components.
SalesforceSoftware EngineerCoding & AlgorithmsTechnical ScreenThis question evaluates understanding of data structures and cache eviction policies, specifically frequency tracking for LFU caches and LRU tie-breaking among equal-frequency items.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteThis problem tests your ability to maintain multiple layers of linked data structures to achieve O(1) time complexity for both access and eviction in an LFU (Least Frequently Used) cache.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteThis problem tests your ability to design a time-aware data structure, manipulate linked structures, and demonstrate mastery over JavaScript's asynchronous execution model and functional programming patterns.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteThis problem tests proficiency with 2D dynamic programming for geometric pattern recognition and 1D dynamic programming for sequence optimization.
SalesforceSoftware EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to solve a classic greedy interval scheduling variation by using sorting and a priority queue to maximize overlapping resource utilization.
SalesforceSoftware EngineerCoding & AlgorithmsTechnical ScreenThis problem tests your ability to optimize mathematical transformations on an integer using greedy strategies or dynamic programming by analyzing the parity and binary representation of the input.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteThis question evaluates algorithm design skills and proficiency with integer operations and decision-making under parity constraints, testing competencies such as bitwise reasoning, greedy and dynamic-programming intuition, and complexity analysis.
SalesforceSoftware EngineerCoding & AlgorithmsTechnical ScreenPartition an array of daily costs into k contiguous weeks to minimize the sum of each week's maximum cost using dynamic programming.
SalesforceSoftware EngineerCoding & AlgorithmsOnsiteThis problem tests your ability to manipulate linked structures to remove duplicates and your algorithmic efficiency in finding the longest string that satisfies two distinct containment constraints.
SalesforceSoftware EngineerCoding & AlgorithmsOnline AssessmentThis question evaluates understanding of singly linked list data structures and in-place node manipulation to remove repeated values while preserving relative order, testing competencies in pointer management and duplicate-detection.
SalesforceSoftware EngineerCoding & AlgorithmsHR Screen