Capital One Data Scientist Coding & Algorithms Interview Questions
Practice 15 real Coding & Algorithms interview questions for Data Scientist roles at Capital One.
"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"
"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"
"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."
"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."
"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."
"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."
"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Find lexicographically smallest string and elimination order
You remember two coding questions from an online assessment. Question 1: Return the lexicographically smallest string after a prefix/suffix reverse Yo...
Fix failing tests and refactor code
You're given a small Python repo. After creating and activating a clean virtual environment, installing requirements, and running "pytest -q", two tes...
Explain Shell Script for Python Virtual Environment Setup
Explain Shell Script for Python Virtual Environment Setup Scenario Shell script for setting up a Python virtual environment during a tech screen Quest...
Review Preprocessing Code and Tests
You are reviewing a small Python preprocessing codebase during an interview. You do not need to write code. Part A: Environment and execution A shell ...
Refactor code and enforce robustness
Code Review and Refactor: Summing a CSV Column Context You are reviewing a short Python script that sums a numeric column from a CSV using pandas. You...
Critique Shell Script for Credit-Card Program Tech Round
Critique Shell Script for Credit-Card Program Tech Round Scenario Tech round for a new credit-card program: candidate is shown a 5-6 line shell script...
Debug and test a Python function in venv
Consider the Python snippet below. """ import math def accumulate(nums, start=0, cache={}): total = start for n in nums: if n % 2 == 0: nums.appen...
Validate Unit-Test Coverage and Identify Missing Scenarios
Validate Unit-Test Coverage and Identify Missing Scenarios Scenario Tech round: reviewing an existing unit-test that exercises the class from Part 2 Q...
Design late-tolerant streaming window aggregator
You receive an unbounded stream of events: (event_time, user_id, category). Events may arrive up to 48 hours late and are not ordered by time. Design ...
Explain Shell Script Line-by-Line for Data Science Workflows
Scenario Technical screening for a Principal Data Scientist: reviewing shell script and Python classes Question Explain, line by line, what the provid...
Optimize invites under capacity constraints
You have n donors (n up to 100,000). For each donor i you know: p_online[i] (probability of donating if emailed), a_online[i] (expected donation condi...
Implement minimal-cost overtime/contractor allocation
You must cover H extra engineering hours this week at minimum cost using employee overtime and optional contractors. Each employee i has a maximum ove...
Automate Python Virtual Environment Setup on Linux Terminal
Scenario Shell script that automates Python virtual-environment setup on a Linux terminal during a tech interview Question Walk through the script lin...
Critique and Test Python Preprocessing Utilities Effectively
Scenario Code review of Python preprocessing utilities (OutlierHandler and three Imputer classes) Question Summarize, at a high level, what the Outlie...
Explain Python Virtual Environment Setup and Function Analysis
Scenario Technical screen where candidate and interviewer jointly walk through Python code snippets used in a data-science repository. Question Show h...