Coding Interview Questions

Study our database of real interview questions and answers verified by hiring managers and candidates.

638 questions
547 companies
27 roles
Last updated Nov 2026

+ Share interview

Given source and destination directory listings, return the files that must be synced: those missing at the destination or differing in size or modification time.
10 months ago
Implement an exchange matching engine.
+210 months ago
Implement a threaded producer-consumer queue, first with a mutex, then optimised with a spin lock; analyse memory ordering and then improve it with a lock-free approach.
3 days ago
Implement an order book across exchanges with add(exchange, price, quantity, side), the best bid and ask on one exchange, and the best bid and ask across all of them.
3 days ago
Code a thread-safe queue in C++.
4 years ago
Get your questions answered
Our question database is made possible by user contributions. What were you asked in your most recent interview?
Share
Write an efficient implementation of a lazily initialised singleton in C++.
3 days ago
Given a list of words and an integer k, generate every combination of k words in which no two words start with the same letter.
3 days ago
Implement void reverse(char* begin, char* end) in C++ and use it to reverse each word of a string in place, keeping the word order.
2 years ago
Given two tables, such as an order list and a user information table, how do you perform an outer join, and how do you handle missing values?
3 days ago
Write code that prints the Cartesian product of the given collections, that is, every combination that takes one element from each.
2 years ago
Given an array of daily prices, find the maximum profit from one buy followed by one sell.
3 days ago
Given an integer n, return how many integers less than n can be written in base 4 using only the digits 0 and 1.
10 months ago
Array A holds m sorted values followed by n empty slots, and array B holds n sorted values. Merge B into A in place so that A is sorted.
3 days ago
Implement k-means in C++.
3 days ago
You are given a function that can add only two single digits. Using it, write a function that adds two non-negative integers supplied as strings and returns the sum as a string.
2 years ago
In Python (pandas), what do concat, groupby and merge each do?
3 days ago
Given an array of integers, find all unique triplets that sum to zero. Write code that runs.
3 days ago
Given two lists of open intervals, each list sorted and non-overlapping, return the list of intersections between them.
3 days ago
Add two binary strings of up to 100,000 digits each and return the sum as a binary string with no leading zeros, without relying on a built-in big-integer type.
5 years ago
How would you draw a random sample from 10 TB of data in Python?
3 days ago

Showing 561-580 of 638

Popular roles

Software Engineer Machine Learning Engineer Data Engineer Data Scientist Quantitative Researcher

Interviewed recently?

Help improve our question database (and earn karma) by telling us about your experience

+ Share interview experience

Trending companies

Coding Interview Questions

Given source and destination directory listings, return the files that must be synced: those missing at the destination or differing in size or modification time.

Implement an exchange matching engine.

Implement a threaded producer-consumer queue, first with a mutex, then optimised with a spin lock; analyse memory ordering and then improve it with a lock-free approach.

Implement an order book across exchanges with add(exchange, price, quantity, side), the best bid and ask on one exchange, and the best bid and ask across all of them.

Code a thread-safe queue in C++.

Write an efficient implementation of a lazily initialised singleton in C++.

Given a list of words and an integer k, generate every combination of k words in which no two words start with the same letter.

Implement void reverse(char* begin, char* end) in C++ and use it to reverse each word of a string in place, keeping the word order.

Given two tables, such as an order list and a user information table, how do you perform an outer join, and how do you handle missing values?

Write code that prints the Cartesian product of the given collections, that is, every combination that takes one element from each.

Given an array of daily prices, find the maximum profit from one buy followed by one sell.

Given an integer n, return how many integers less than n can be written in base 4 using only the digits 0 and 1.

Array A holds m sorted values followed by n empty slots, and array B holds n sorted values. Merge B into A in place so that A is sorted.

Implement k-means in C++.

You are given a function that can add only two single digits. Using it, write a function that adds two non-negative integers supplied as strings and returns the sum as a string.

In Python (pandas), what do concat, groupby and merge each do?

Given an array of integers, find all unique triplets that sum to zero. Write code that runs.

Given two lists of open intervals, each list sorted and non-overlapping, return the list of intersections between them.

Add two binary strings of up to 100,000 digits each and return the sum as a binary string with no leading zeros, without relying on a built-in big-integer type.

How would you draw a random sample from 10 TB of data in Python?

Explore questions by company

Explore questions by role

Follow Us