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9.6k Questions 505 Companies08.05.2026
Showing 20 results
Role
DoorDash logo
DoorDash
Medium
Software Engineer

Compute nearest dashmart and busiest assignments

Compute nearest dashmart and busiest assignments You are given an m x n grid of characters where 'D' marks a dashmart, 'X' marks an impassable cell, a...

Coding & Algorithms
7
0
75 people solved
Jul 17, 2025
Optiver logo
Optiver
Medium
Software Engineer

Solve three mini-game algorithm tasks

Solve three mini-game algorithm tasks Solve three mini-game algorithm tasks: (a) Move-House Puzzle: Given initial and target arrangements of N labeled...

Coding & Algorithms
12
0
86 people solved
Jul 17, 2025
Amazon logo
Amazon
Medium
Machine Learning Engineer

Implement inventory allocation with backorders

Implement inventory allocation with backorders Design and implement a function to process an event stream for an e-commerce marketplace. Input: ( 1) i...

Coding & Algorithms
1
0
27 people solved
Jul 17, 2025
Stripe logo
Stripe
Medium
Software Engineer

Implement tiered shipping calculator

Implement tiered shipping calculator Implement in JavaScript a shipping-cost calculator with three progressively richer pricing models based on a conf...

Coding & Algorithms
3
0
35 people solved
Jul 17, 2025
Circle logo
Circle
Medium
Software Engineer

Implement a simplified multi-level banking system

Implement a simplified multi-level banking system Implement a simplified banking system with multi-level requirements. All operations accept a stringi...

Coding & Algorithms
9
0
83 people solved
Jul 17, 2025
TikTok logo
TikTok
Medium
Software Engineer

Explain Java DI, AOP, and transactions

Explain how dependency injection and AOP proxies are implemented in a modern Java framework such as Spring: bean lifecycle (creation, post-processing,...

Coding & Algorithms
2
0
18 people solved
Jul 17, 2025
xAI logo
xAI
Medium
Machine Learning EngineerIntern

Validate normalized palindromes with variants

Implement a function isNormalizedPalindrome(s) that returns true if s reads the same forward and backward after removing non‑alphanumeric characters a...

Coding & Algorithms
14
1
109 people solved
Jul 17, 2025
Abnormal Security logo
Abnormal Security
Medium
Software Engineer

Design a duplicate-file removal algorithm

Design a duplicate-file removal algorithm Your filesystem contains millions of photos. Duplicates are strictly byte-identical files (no ML/CV similari...

Coding & Algorithms
10
0
118 people solved
Jul 16, 2025
LinkedIn logo
LinkedIn
Medium
Machine Learning Engineer

Compute total covered interval length

Compute total covered interval length Given a list of integer intervals [l, r) (half-open), compute the total length covered by at least one interval....

Coding & Algorithms
13
0
106 people solved
Jul 16, 2025
Meta logo
Meta
Medium
Data Engineer

Write SQL for library analytics

Given a library database, write SQL to answer the following: 1) Count the number of books that are currently not returned (i.e., still checked out) an...

Data Manipulation (SQL/Python)
1
0
14 people solved
Jul 16, 2025
Airbnb logo
Airbnb
Medium
Software Engineer

Design refundable transaction ledger and prioritization rules

Design and implement a transaction ledger that ingests a stream of records where each record is either a payment or a refund. Each payment has {id, us...

Coding & Algorithms
32
0
298 people solved
Jul 16, 2025
Morgan Stanley logo
Morgan Stanley
Medium
Software Engineer

Count decodings of a digit string

Count decodings of a digit string You are given a non-empty digit string s consisting of characters '0'–'9' and a mapping where 1->'a', 2->'b', ..., 2...

Coding & Algorithms
3
0
37 people solved
Jul 16, 2025
Citadel logo
Citadel
Medium
Software Engineer

Solve two DS&A optimization problems

Problem 1 — Maximize alternating-sum over four array partitions: Given an integer array arr[1..n] (1-based). Choose indices a, b, c with 1 ≤ a ≤ b ≤ c...

Coding & Algorithms
8
0
130 people solved
Jul 16, 2025
LinkedIn logo
LinkedIn
Medium
Machine Learning Engineer

Find shortest word transformation with caching

Find shortest word transformation with caching You are given a start word and an end word of equal length, and a dictionary of valid words. In one mov...

Coding & Algorithms
10
0
94 people solved
Jul 16, 2025
Optiver logo
Optiver
Medium
Software Engineer

Detect currency arbitrage with costs

You are given a K×K matrix R of currency exchange rates where R[i][j] is the amount of currency j obtainable for one unit of currency i, and R[i][i] =...

Coding & Algorithms
36
0
261 people solved
Jul 16, 2025
TikTok logo
TikTok
Medium
Software Engineer

Parse chemical formula with multipliers

Parse chemical formula with multipliers Given a string representing a chemical formula, parse it and return the total count of each element. The formu...

Coding & Algorithms
3
0
34 people solved
Jul 16, 2025
Amazon logo
Amazon
Medium
Software Engineer

Describe achievements, ambiguity, conflict, efficiency, challenges

Describe achievements, ambiguity, conflict, efficiency, challenges Behavioral Technical Screen — Multi-part Prompt Context: You are interviewing for a...

Behavioral & Leadership
2
0
30 people solved
Jul 16, 2025
Microsoft logo
Microsoft
Medium
Software Engineer

Compute sum of longest positive subarray

Compute sum of longest positive subarray Given an integer array that may contain positive and negative numbers, find the sum of the longest contiguous...

Coding & Algorithms
5
0
46 people solved
Jul 16, 2025
Meta logo
Meta
Medium
Software Engineer

Implement range-sum tree and sort merged lists

Implement range-sum tree and sort merged lists 1) Given a binary tree whose nodes store integer values, and two integers low and high defining an incl...

Coding & Algorithms
4
0
38 people solved
Jul 16, 2025
Morgan Stanley logo
Morgan Stanley
Medium
Software Engineer

Compute minimal cost to merge numbers

Compute minimal cost to merge numbers Given an array of positive integers, you may repeatedly perform the following operation until one number remains...

Coding & Algorithms
4
0
41 people solved
Jul 16, 2025