Capital One Coding Interview Questions: 24 Tagged Problems
24 coding problems tagged Capital One — 8 easy · 13 medium · 3 hard — with solutions in 13 languages. Plus a 2-week study plan by topic.
- Problems: 24
- By difficulty: 8 easy · 13 medium · 3 hard
- Languages: JavaScript, TypeScript, Python, Java, C++, C, C#, Go, Kotlin, Swift, Rust, PHP and Ruby
- Cost: Free on every plan; sign in to run and submit
24 problems the CodeKairo catalogue tags as commonly asked in Capital One's coding rounds — 8 easy, 13 medium and 3 hard — each judged by hidden tests in 13 languages. The most common topics among them are Arrays (18), Math (8) and Strings (7). Tagged for Capital One and no other company: Simplify Path. The tag is the catalogue's own annotation of where a problem tends to come up — not a list published by Capital One, which CodeKairo is not affiliated with.
Capital One study plan by topic
All 24 problems tagged Capital One over 2 weeks, about 12 h 45 min of solving, grouped by technique in the order they build on each other — Arrays, Strings, Hash Table and Counting and 14 more.
Week 1: Arrays, Strings, Hash Table +8
12 problems on Arrays, Strings, Hash Table, Counting, Math, Two Pointers, Sorting, Stack, Monotonic Stack, Monotonic Queue and Matrix, easiest first within each topic.
- Monotonic Array Easy
- License Key Formatting Easy
- Two Sum Easy
- Minimum Operations to Write the Letter Y on a Grid Medium
- Palindrome Number Easy
- Count Alternating Subarrays Medium
- Container With Most Water Medium
- Minimum Time Difference Medium
- Simplify Path Medium
- Largest Rectangle in Histogram Hard
- Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit Medium
- Rotate Image Medium
Week 2: Simulation, Intervals, Number Theory +4
12 problems on Simulation, Intervals, Number Theory, Union Find, Dynamic Programming, Rolling Hash and Binary Indexed Tree, easiest first within each topic.
- Fizz Buzz Easy
- Add Strings Easy
- Count Operations to Obtain Zero Easy
- Spiral Matrix Medium
- Rotating the Box Medium
- Text Justification Hard
- Merge Intervals Medium
- Four Divisors Medium
- Number of Islands Medium
- Best Time to Buy and Sell Stock Easy
- Count Prefix and Suffix Pairs II Hard
- Minimum Absolute Difference Between Elements With Constraint Medium
All problems tagged Capital One
Easy (8)
- Count Operations to Obtain Zero Math, Simulation
- Monotonic Array Array
- License Key Formatting String
- Add Strings Math, String, Simulation
- Best Time to Buy and Sell Stock Array, Dynamic Programming
- Fizz Buzz Math, String, Simulation
- Palindrome Number Math
- Two Sum Array, Hash Table
Medium (13)
- Minimum Operations to Write the Letter Y on a Grid Array, Hash Table, Matrix
- Minimum Absolute Difference Between Elements With Constraint Array, Binary Search, Ordered Set
- Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit Array, Sliding Window, Monotonic Queue
- Four Divisors Array, Math, Number Theory
- Minimum Time Difference Array, Math, String
- Rotating the Box Array, Matrix, Two Pointers
- Count Alternating Subarrays Array, Math, Dynamic Programming
- Merge Intervals Array, Sorting, Intervals
- Number of Islands Array, Matrix, Depth-First Search
- Spiral Matrix Array, Matrix, Simulation
- Rotate Image Array, Matrix, Math
- Simplify Path String, Stack
- Container With Most Water Array, Two Pointers, Greedy
Hard (3)
- Count Prefix and Suffix Pairs II Array, String, Trie
- Text Justification Array, String, Simulation
- Largest Rectangle in Histogram Array, Stack, Monotonic Stack
Topics Capital One asks most
- Arrays 18 problems
- Math 8 problems
- Strings 7 problems
- Simulation 6 problems
- Matrix 5 problems
- Hash Table 2 problems
- Two Pointers 2 problems
- Sorting 2 problems
- Stack 2 problems
- Ordered Set 2 problems
- Dynamic Programming 2 problems
- Counting 1 problem