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All Questions

Browse our full set of technical interview questions for software engineering jobs. They touch on a mix of algorithms, coding, and big-o notation.

1
Apple Stocks »

Figure out the optimal buy and sell time for a given stock, given its prices yesterday. keep reading »

2
Product of All Other Numbers »

For each number in an array, find the product of all the other numbers. You can do it faster than you'd think! keep reading »

3
Highest Product of 3 »

Find the highest possible product that you can get by multiplying any 3 numbers from an input array. keep reading »

4
Merging Meeting Times »

Write a function for merging meeting times given everyone's schedules. It's an enterprise end-to-end scheduling solution, dog. keep reading »

5
Making Change »

Write a function that will replace your role as a cashier and make everyone rich or something. keep reading »

6
Rectangular Love »

Find the area of overlap between two rectangles. In the name of love. keep reading »

7
Temperature Tracker »

Write code to continually track the max, min, mean, and mode as new numbers are inserted into a tracker class. keep reading »

8
Balanced Binary Tree »

Write a function to see if a binary tree is 'superbalanced'--a new tree property we just made up. keep reading »

9
Binary Search Tree Checker »

Write a function to check that a binary tree is a valid binary search tree. keep reading »

10
2nd Largest Item in a Binary Search Tree »

Find the second largest element in a binary search tree. keep reading »

11
MillionGazillion »

I'm making a new search engine called MillionGazillion(tm), and I need help figuring out what data structures to use. keep reading »

12
Find in Ordered Set »

Given an array of numbers in sorted order, how quickly could we check if a given number is present in the array? keep reading »

13
Find Rotation Point »

I wanted to learn some big words to make people think I'm smart, but I messed up. Write a function to help untangle the mess I made. keep reading »

14
Inflight Entertainment »

Writing a simple recommendation algorithm that helps people choose which movies to watch during flights keep reading »

15
Compute nth Fibonacci Number »

Computer the nth fibonacci number. Careful--the recursion can quickly spin out of control! keep reading »

16
The Cake Thief »

You've hit the motherload: the cake vault of the Queen of England. Figure out how much of each cake to carry out to maximize profit. keep reading »

17
JavaScript Scope »

There's something tricky going on with scope in this JavaScript. Can you guess what will get logged to the console? keep reading »

18
What's Wrong with This JavaScript? »

There's a tricky bug in this JavaScript. Can you find it? keep reading »

19
Queue Two Stacks »

Implement a queue with two stacks. Assume you already have a stack implementation. keep reading »

20
Largest Stack »

You've implemented a Stack class, but you want to access the largest element in your stack from time to time. Write an augmented LargestStack class. keep reading »

21
The Stolen Breakfast Drone »

In a beautiful Amazon utopia where breakfast is delivered by drones, one drone has gone missing. Write a function to figure out which one is missing. keep reading »

22
Delete Node »

Write a function to delete a node from a linked list. Turns out you can do it in constant time! keep reading »

23
Does This Linked List Have A Cycle? »

Check to see if a linked list has a cycle. We'll start with a simple solution and move on to some pretty tricky ones. keep reading »

24
Reverse A Linked List »

Write a function to reverse a linked list in-place. keep reading »

25
Kth to Last Node in a Singly-Linked List »

Find the kth to last node in a singly-linked list. We'll start with a simple solution and move on to some clever tricks. keep reading »

26
Reverse String in Place »

Write a function to reverse a string in-place. keep reading »

27
Reverse Words »

Write a function to reverse the word order of a string, in-place. It's to decipher a supersecret message and win the war. keep reading »

28
Parenthesis Matching »

Write a function that finds the corresponding closing parenthesis given the position of an opening parenthesis in a string. keep reading »

29
Bracket Validator »

Write a super-simple JavaScript parser that can find bugs in your intern's code. keep reading »

30
Permutation Palindrome »

Check if any permutation of an input string is a palindrome. keep reading »

31
Recursive String Permutations »

Write a recursive function of generating all permutations of an input string. keep reading »

32
Top Scores »

Efficiently sort numbers in an array, where each number is below a certain maximum. keep reading »

33
Which Appears Twice »

Find the repeat number in an array of numbers. Optimize for runtime. keep reading »

34
Word Cloud Data »

You're building a word cloud. Write a function to figure out how many times each word appears so we know how big to make each word in the cloud. keep reading »

35
In-Place Shuffle »

Do an in-place shuffle on an array of numbers. It's trickier than you might think! keep reading »

36
Single Riffle Shuffle »

Write a function to tell us if a deck of cards is a single riffle of two other halves. keep reading »

37
Simulate 5-sided die »

Given a 7-sided die, make a 5-sided die. keep reading »

38
Simulate 7-sided die »

Given a 5-sided die, make a 7-sided die. keep reading »

39
Two Egg Problem »

A building has 100 floors. Figure out the highest floor an egg can be dropped from without breaking. keep reading »

40
Find Repeat, Space Edition »

Figure out which number is repeated. But here's the catch: optimize for space. keep reading »

41
Find Repeat, Space Edition BEAST MODE »

Figure out which number is repeated. But here's the catch: do it in linear time and constant space! keep reading »

42
Find Duplicate Files »

Your friend copied a bunch of your files and put them in random places around your hard drive. Write a function to undo the damage. keep reading »

43
Merge Sorted Arrays »

Write a function for consolidating cookie orders and taking over the world. keep reading »

44
URL Shortener »

Design a URL shortener, like bit.ly keep reading »

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