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9.6k Questions 505 Companies08.05.2026
Showing 20 results
Role
Optiver logo
Optiver
Easy
Data Scientist

Stone Pile Doubling Game: Can One Pile Be Emptied?

You are given two piles of stones containing a and b stones respectively (both piles start non-empty). You repeatedly apply the following move: - Let ...

Coding & Algorithms
0
0
2 people solved
Jul 26, 2025
Amazon logo
Amazon
Medium
Software Engineer

Solve median extremes and segment flips

Solve median extremes and segment flips Part A — Sliding-window median extremes: - Input: an integer k (1 ≤ k ≤ n) and an array nums of length n. - Fo...

Coding & Algorithms
2
0
25 people solved
Jul 26, 2025
Kneron logo
Kneron
Medium
Software Engineer

Count IoT devices matching date and threshold

Implement function numDevices(statusQuery, threshold, dateStr) that returns the number of IoT devices from a paginated REST API that were added in the...

Data Manipulation (SQL/Python)
0
0
8 people solved
Jul 26, 2025
Kneron logo
Kneron
Medium
Software Engineer

Compute sum of minima with removals

Compute sum of minima with removals You are given an array weights[0..n-1] of positive integers representing product weights in a line. Repeat until n...

Coding & Algorithms
2
0
21 people solved
Jul 26, 2025
Meta logo
Meta
Medium
Software Engineer

Solve increasing sequence and path problems

Solve increasing sequence and path problems Answer the following related tasks about increasing sequences and paths: a) Contiguous subarray: Given an ...

Coding & Algorithms
3
0
27 people solved
Jul 26, 2025
Bloomberg logo
Bloomberg
Medium
Software Engineer

Create SQL report of top extensions by weekday

You are given a PostgreSQL table service_access_log with columns: method TEXT (HTTP verb), path TEXT (URL path that may include a filename and optiona...

Data Manipulation (SQL/Python)
0
0
4 people solved
Jul 26, 2025
Meta logo
Meta
Medium
Software Engineer

Produce asymmetric side views of a binary tree

Produce asymmetric side views of a binary tree Given a binary tree, output two sequences: ( 1) Left-bottom-up view: for each depth, the first node vis...

Coding & Algorithms
2
0
43 people solved
Jul 26, 2025
Citibank logo
Citibank
Medium
Data Scientist

Write SQL for rolling default rates

Write a SQL query to compute 12‑month rolling default rates by customer segment. Assume table loans(month DATE, segment TEXT, defaults INT, accounts I...

Data Manipulation (SQL/Python)
0
0
4 people solved
Jul 26, 2025
Meta logo
Meta
Medium
Software Engineer

Remove adjacent duplicate groups repeatedly

Remove adjacent duplicate groups repeatedly Given a string s, repeatedly delete any maximal contiguous group of identical characters whose length is a...

Coding & Algorithms
3
0
37 people solved
Jul 26, 2025
Amazon logo
Amazon
Medium
Software Engineer

Compute unique visitors by department

You have two tables: products(product_id, department, category, subcategory) where department > category > subcategory form a parent–child hierarchy, ...

Data Manipulation (SQL/Python)
0
0
8 people solved
Jul 26, 2025
Nash AI logo
Nash AI
Medium
Software Engineer

Design OOD for probabilistic Minesweeper

Design OOD for probabilistic Minesweeper Object-Oriented Design: Minesweeper with Per-Cell Mine Probabilities Context Design an object-oriented Minesw...

System Design
6
0
46 people solved
Jul 26, 2025
Oracle logo
Oracle
Medium
Software Engineer

Determine if robot path is bounded

Determine if robot path is bounded A robot starts at (0, 0) facing North on an infinite grid. It executes a string s consisting of 'G' (move forward 1...

Coding & Algorithms
7
0
69 people solved
Jul 26, 2025
Snowflake logo
Snowflake
Medium
Software Engineer

Transform tree with subtree sum mapping

Transform tree with subtree sum mapping You are given the roots of two complete binary trees T1 and T2 that have identical structure (same shape and n...

Coding & Algorithms
7
0
59 people solved
Jul 26, 2025
C3 AI logo
C3 AI
Medium
Data Scientist

Decompress an encoded string

Decompress an encoded string Given an encoded string, return its decoded (decompressed) form. Use the following encoding rule: - A positive integer \(...

Coding & Algorithms
2
0
37 people solved
Jul 25, 2025
Two Sigma logo
Two Sigma
Medium
Software Engineer

Maximum Group of Pairwise Strangers in an Acquaintance Tree

You are given a social network of n people, labeled 0 through n - 1. For some pairs of people, it is known that the two people in the pair know each o...

Coding & Algorithms
0
0
5 people solved
Jul 23, 2025
Optiver logo
Optiver
Medium
Software Engineer

Validate a Binary Tree Built from Directed Edges

Validate a Binary Tree Built from Directed Edges You are given a list of directed edges. Each edge is a pair (parent, child) of positive-integer node ...

Coding & Algorithms
0
0
5 people solved
Jul 23, 2025
Optiver logo
Optiver
Medium
Software Engineer

Count the Days Between Two Dates

Count the Days Between Two Dates You are given two calendar dates as strings in YYYY-MM-DD format. Return the number of days between them as a non-neg...

Coding & Algorithms
0
0
8 people solved
Jul 23, 2025
Two Sigma logo
Two Sigma
Hard
Software Engineer

Compute maximum currency exchange rate

Compute maximum currency exchange rate You are given a set of currencies and the direct exchange rates between some pairs of them. Each direct exchang...

Coding & Algorithms
17
0
147 people solved
Jul 20, 2025
Zillow logo
Zillow
Medium
Machine Learning Engineer

Find max min-plus-max over all subarrays

Find max min-plus-max over all subarrays You are given an array arr of n integers. A subarray is a contiguous non-empty segment of the array. For any ...

Coding & Algorithms
5
0
37 people solved
Jul 18, 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