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3M Interview Questions

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Pick A Sign

We're given an array of positive integers like the following: js 2, 1, 3, 2 Imagine that we're allowed to make each element of the array either a positive or negative number, indicated by a signage either a plus or minus sign that appears before it. If we sum up all the si...

Difficulty: 7/10

Serialize and Deserialize a Binary Tree

Given a binary tree representation, can you come up with a method to serialize the tree and then deserialize it to get the exact same tree? What is Serialization and Deserialization? Serialization is a process that converts a data structure to a suitable format that can be stored either ...

Difficulty: 8/10

Split Set to Equal Subsets

We're given a set in the form of an array with a unique integers. Can you write a function that tells us whether it can be separated into two subsets whose elements have equal sums? Here's an example: 5, 9, 7, 21 : The below would return true because newSet can be divided into 5, 9, 7 ...

Difficulty: 5/10

Remove Duplicates From Array

Given an array, return another array with just the ordered unique elements from the given array. In other words, you're removing any duplicates. Note: Order needs to be preserved, so no sorting should be done. And the order should be maintained with the first occurrence of the element in the given...

Difficulty: 4/10

Nth Smallest Number in a Stream

Many modern programming languages have the notion of a stream. A stream is a resource _that's broken down_ and sent usually over a network in small chunks. Imagine a video that's playing it would be inefficient to need to download an entire 1 gigabyte movie before being able to watch it. Inste...

Difficulty: 7/10

Text Justification

Can you justify input text represented by an array of words so it looks pretty when printed and the whitespaces are balanced? For example, in the above image, we have an input array of "wow", "so", "cool", "is", "algodaily!" . This is a list of words we need to properly arrange, with the ideal ...

Difficulty: 9/10

Subsets Summing Zero

Given an array of positive and negative integers like the following: js const arr 3, 5, 2, 4, 7, 1, 6, 8, 8, 4 Can you write a method findSumZeroSubsets to return the starting and ending indexes of all subarrays in it that sum up to zero? **Note**: There are 3 terms that...

Difficulty: 7/10

Longest Substring With No Duplicate Characters

Given a string of characters, can you find the longest substring of the string that has no repeating characters? An example is shown below: js lengthOfLongestSubstring "abracadabar" 4 because it is 'brac' Constraints Length of the string 100000 The string ...

Difficulty: 5/10

Lamps and Houses

On a given street, there's a bunch of houses and lamps nearby. It looks kind of like the following H being houses, L being lamps : L H L H H 0 1 2 3 4 We decide to represent this with two arrays: one being the positions of the houses, and the other the positions of the lamps. From the ...

Difficulty: 8/10

Introduction to AWS

Introduction to Cloud Computing Cloud computing is a model for delivering computing resources, including servers, storage, databases, networking, software, and analytics, over the internet. It allows organizations to access compute power and storage on demand, without having to invest in physica...

Difficulty: 5/10

Normalization in SQL

Normal Forms Introduction _**Normalization** is a process that is used for organizing the data in the database by removing data redundancy and improving data integrity. The primary goal of normalizing a given relation is to get rid of Insert, Delete, and Update abnormalities._ This **multi s...

Difficulty: 5/10

JavaScript Basics

Introduction to JavaScript JavaScript is a high level programming language that is widely used for frontend web development. It is a key technology for creating interactive and dynamic websites. JavaScript runs on the client side, meaning it is executed by the user's web browser. This allows f...

Difficulty: 5/10

Interview Reports

3M Interview: 8 Must Know Questions and Answers...

3M Interview Questions and Answers. Here we will discuss how to successfully answer potential interview questions at 3M Company.

32 3M Interview Questions (with Answers)...

Practice 32 3M Interview Questions with professional interview answer examples with advice on how to answer each question. With an additional 63 professionally written interview answer examples.