# 8 Questions About the Array Data Structure for a Job Interview (With Sample Answers)

**8 Questions About the Array Data Structure for a Job Interview (With Sample Answers)**

You need to know a lot about data structures, programming languages, and algorithmic functions to get a job in programming. How array data structures work in a program is one of the most basic things a programmer needs to know. Arrays, how they are used, and how they are written may come up in interviews for programming jobs. This article shows you how to answer common questions about arrays that you might be asked in an interview.

**What is an array? It is a type of data structure.**

An array is a type of data structure that lets code store and organize data. Since arrays are static functions, you can’t change how long they are once you’ve made one. Programmers find it easier to find elements or numbers in a known index when they use arrays. To make an array, you list each element, put commas between them, and put the list in square brackets.

**8 questions about arrays, with examples of how to answer them**

Here are some sample answers to eight common questions about arrays to help you get ready for your interview:

**How do you change the order of an array?**

Interviewers might ask you to explain how to flip a list. This question checks how well you understand arrays and how well you can use them in your programming.

One possible answer:

“There are different ways to change the direction of an array. You can make a temporary array by making a reverse function and inserting a new array with the same parameters and data as the first. The original array’s elements can also be switched. You can do this by swapping 1 with n, 2 with n 1, and so on until you get to the end of the array. You could also turn the array into a list and use a function for collections called “reverse list” on the list “*

**What makes a linked list different from an array?**

If an interviewer asks you to explain the main differences between an array and a linked list, they may be trying to see if you know the basics of data structures and when to use each one. Giving a full answer shows the interviewer that you can think about when to use different structures.

Here’s what I mean: “The way an array is set up can’t be changed by a programmer, so it can’t be changed. You have more options and can change the size with a linked list. A linked list can also keep getting bigger and bigger, but an array can’t. You can also remember these lists in more ways. A linked list can use memory that is in different places than an array, which can only use memory that is all in one place. I use a linked list when the size of a set changes. I use an array if the size of a set doesn’t change. Arrays are better for fixed sets and are better when using an index to quickly find data.”

**What are the benefits and drawbacks of using arrays?**

This question lets you show how well you understand arrays and how logically you can think. You can show that you know when arrays are useful and when another method is better by answering this question.

Here’s what I mean: “Arrays can be used to sort a lot of things at once and to set up other data structures like stacks, queues, and trees. The main reason to use an array is that you can get to the elements by using the index. The biggest problem with arrays is that they always have the same number of elements. I only use them when I know how big the data set is before I write the array.”

**How do I figure out which number is missing from a list of numbers from 1 to 100?**

Interviewers often ask this question to see how well you know the functions that can be used by programmers to change or fix arrays. This question may also show how good you are at solving problems, since the answer can change depending on the exact array elements or how they are put together. You can also show the interviewer that you are flexible and know a lot if you have answers for all possible problems.

Here’s what I mean: “Using this function to find the sum of the series is the best way to find a missing integer:

**n (n + 1) / 2**

This function only works if the array doesn’t have any numbers that are missing or have more than one duplicate. To find missing integers in an array with duplicates, you can sort the array and look for elements that are the same.”

**How do you take something out of an array?**

This is a simple question that interviewers ask to see how knowledgeable you are and how well you can solve problems. Since you can’t just take an element out of an existing array, the interviewer wants you to come up with an alternative solution and talk about the problem the question poses.

Here’s what I mean: “You can’t just take things out of the original array because arrays are sets whose sizes can’t change. If you want to get rid of an element, you should make a new array. You could put copies of the items in the first array into this one, leaving only the one you want to get rid of out of this one.”

**How do you find the index of an element in an array?**

Interviewers may ask you to explain how to find the index of an element as a way to see how well you can write code and use the right functions. By showing that you know each step in depth, you can show the interviewer how skilled and experienced you are.

Here’s what I mean: “To find the index of an array element, you can either use a linear search or a binary search. A linear search is a function that starts with the first element and goes through each element one by one until it finds the element that matches the one that was asked for. Once it finds the right element, it gives back the index.

A binary search, on the other hand, divides the array in half over and over again until the median of the interval matches the element you want and gives you the index. If the array is already in order, you can use a binary search function. A linear search is usually the best way to find what you’re looking for when the array isn’t in order.”

**7.How can I combine two arrays that have been sorted into one?**

During a programming interview, the employer might ask you to show how good you are at more difficult tasks like merging arrays. Knowing how to do this job and being able to explain the steps shows the interviewer that you are skilled and have a lot of experience.

Here’s what I mean: “To combine two arrays, you can make a new array with the same size as the sum of the two old arrays. You can put the items from the first array into the second one. Then you can go through the second array and add its items to the new one.”

**8. How do you change the shape of a two-dimensional array?**

Interviewers may ask you questions about 2D arrays to see how well you understand technology. You can show the interviewer that you know how programming works and what its structures are by giving a full answer and using the right words for arrays, matrices, and rings.

Here’s what I mean: “You can rotate a 2D array, or matrix, by starting with the outermost element and rotating each ring of elements one at a time. To turn a ring, you move the pieces in the top row first, then the pieces in the last column, the bottom row, the first column, and finally the pieces in the top row. For every ring, you do this. Most of the time, you can use a series of loop functions to do this rotation until you get the result you want.”