Facebook Interview Questions And Answers To Pump Up Your Prep (2023)

Facebook is an online social networking site owned by an American company, Meta Platforms. Founded by Mark Zuckerberg in 2004, Facebook has been named the Best Place to Work in Tech by Glassdoor. This is the reason the company receives about 250,000 job applications each year. Standing out amongst these many job seekers is difficult, especially for a company that has a well-designed and stringent recruitment process in place.

Hence, for engineers who want to join this company, cracking the Facebook selection process can be tricky. In this article, we will shed light on some of the important Facebook interview questions to take you closer to becoming a part of this company.

Facebook Interview Questions and Answers

Before we delve deeper into the Facebook interview questions, let us quickly go through the various stages involved in the Facebook interview process.

• Technical phone interview: Focuses on basic problem-solving and fundamental knowledge of programming languages.
• Onsite interviews for coding: To assess the coding skills, the candidate is made to solve coding problems on paper or on a whiteboard.
• Onsite system design interviews: This round candidates' skill sets for coming up with efficient high-level design architectures for real-life products. This round may be skipped for fresh engineering graduates.
• Onsite behavioral interview round: This round is meant to evaluate if the candidate is a good cultural for Facebook. So the focus is more on soft skills rather than technical acumen.

Facebook firmly believes in recruiting candidates who resonate with what the company stands for. So, the company clearly spells out its core values to provide a guideline for hiring managers while they select candidates for various roles.

Let's now dig into the important Facebook interview questions to help you prepare for the rigorous selection process.

Facebook Interview Questions: Technical

Following Facebook interview questions will give you a good idea regarding all the important topics that you must prepare for the interview rounds of engineering job profiles.

1. Explain the process to convert any integer value between 1 and 3999 into a Roman number.

To convert any integer value between 1 and 3999 to its Roman numeral equivalent, the following steps can be followed:

1. Compare the integer with base values 1000, 900, 500, 400, 50, 40, 10, 9, 5, 4, and 1 in the respective order.
2. The value that is the closest, smaller or equal, will serve as the initial base value.
3. Now, divide the given number by the initial base value.
4. The corresponding Roman Symbol for the initial base value will be repeated quotient times, while the remainder will follow Step 1
5. The process will be iterated until the remainder becomes 0

2. What is a binary search tree?

A Binary Search Tree is a node-based binary tree data structure. The features of Binary Search Tree are:

1. The left subtree of a node contains only nodes with keys lesser than the node’s key.
2. The right subtree of a node contains only nodes with keys greater than the node’s key.
3. The left and right subtree each must also be a binary search tree.

3. How will you check that the sum of 2 elements in an array is equal to the given number x?

The following algorithm can be followed for checking whether the sum of 2 elements in an array equals the given number x or not:

1. Sort the given array in decreasing order
2. Initialize two index variables:
3. l = 0 to the leftmost index
4. r = ar_size-1 to the rightmost index
5. While l<r:
6. Return 1, if A[l] + A[r] == sum
7. l++, if A[l] + A[r] < sum
8. Otherwise r--
9. Continue looping step 3 until all elements in the array are exhausted

4. You are given a binary tree. Explain how you will find its minimum depth.

The approach to finding the minimum depth of a binary tree involves traversing the given binary tree. So, every node needs to be checked if it is a leaf node or not. There may be two conditions:

If it is a leaf node, then return 1

If not, then follow the following steps:

• Recur for the right subtree if the left subtree is NULL
• Recur for the left subtree if the right subtree is NULL
• Take the minimum of the two depths if both the left and right subtrees are not NULL

5. How will you convert a ternary expression to a binary tree?

It would require traversing the string and making the first character the root node. Then the following steps can be followed:

1. Add the next character as the left child of the root (when encountering the ‘?’ symbol)
2. Add the next character as the right child of the root (when encountering the ‘.’ symbol)
3. Repeat steps 1 and 2 until all elements of the string are traversed

6. Explain polymorphism in C++

Polymorphism in C++ refers to a situation when the same entity (which can be a function or an object) behaves differently in different situations. In other words, a single action is performed in different ways. Polymorphism has two types:

• Compile-time polymorphism
• Runtime Polymorphism

7. Explain pickling and unpickling in Java.

In Java, 'pickling' is the process whereby a Python object hierarchy is converted into a byte stream. On the other hand, 'unpickling' is the inverse operation, whereby a byte stream is converted back into an object hierarchy.

8. How to find the count of the smallest subarray of a given array with a sum greater than the given value x.

The algorithm that can be followed is:

1. Use two nested loops for finding the smallest subarray of a given array with a sum greater than the given value x.
2. While the outer loop will pick a starting element, the inner loop will consider all elements as the ending element.
3. You must note that each time the sum of the elements present between the current start and end becomes more than the given number x, the result is updated if the present length is smaller than the previous smallest length.

9. Explain how to find the nth term in Count and Say sequence.

To begin with, we need to generate all terms from 1 to n. The first two terms are initialized as 1 and 11. The 3rd term is generated from the 2nd, 4th from the 3rd, and so on. To generate the next term, we need to scan the previous term.

10. Can you find non-matching characters in a string?

Non-matching characters in a string can be found in the following manner:

1. Hash Map data structure is taken which works with the key-value pair.
2. Loop the string, character by character, and verify if that character of the string exists in the hash map or not.
3. If the result is true, the counter for the character in the hash map is increased, or else then put a count as 1.
4. Once the loop ends, then the Hash map is traversed, and print the characters with a count equal to 1.

The above technical questions will provide you with a rough idea of the type of questions you could be asked in the Facebook selection rounds. However, along with preparing for the technical interviews, Facebook's HR round also needs to be given due attention. Below are some commonly asked Facebook interview questions for the behavioral interview round.

Facebook Interview Questions: Behavioral Round

The behavioral interview questions asked during Facebook interview rounds intend to assess the soft skills of tech professionals. This is because Facebook seeks a candidate who is a good team player, can manage to work in a cross-functional team, and in short fits well in Facebook's team culture. The questions are thus designed to understand different aspects of the candidate's personality. In this section, we will cover some important Facebook interview questions for the HR round that you must glance through before going to this stage of the selection process.

What are the duties that you dislike doing?

To perform well in the behavioral interview round, you must be ready to face the trickiest Facebook interview questions with ease. The trick to answering these questions is, to be honest, but avoid giving strong reactions. For example, saying you don't like doing tasks that are repetitive can be a safe option. It just reflects that you are a person who likes to explore newer options

Was there a time when a project took you longer than expected?

In software engineering, many times projects take longer time than expected. Thus, through these types of questions, the interviewer wants to understand your way of dealing with such situations. To answer these questions, you must highlight:

• Your capacity to prioritize work
• Your motive for sticking to deadlines
• Your understanding of urgent and important work

Share an incident where you exhibited your leadership qualities.

Through such Facebook interview questions, the hiring manager wants you to talk about your relationship-building skills, judgment power, capacity to take responsibility or initiative, and your confidence level. Hence, narrate an incident where you can cover all these points well.

Tell us about a time when you were in a fix and how did you overcome the same?

The question is intended to understand your capacity to resolve blocks and strategize when stuck in stressful situations.

To frame an ideal answer to this question, you can talk about the effective strategies that you come up with during stressful situations. Explain the process you follow to frame a solution to deal with a difficult situation.

Tell us about a time when you had to learn or pick up a skill quickly.

The interviewer wants to assess how well you can adapt and perform in challenging situations and unfavorable environments.

Hint: You can state an incident where you learned a technical skill in record time as it was required to deliver a project.

Foolproof tips to nail the Facebook interview questions

Facebook firmly believes in its core values. In fact, the candidate who closely relates to these fundamental values of the company is the most potential one for Facebook. The following pointers will provide you with a gist of what Facebook is actually looking for in a candidate.

• Boldness: Facebook believes in the power of taking calculated risks. Hence, candidates who challenge the status quo are best suited for the company.
• Focus on Impact: If you are good at identifying big problems and framing innovative solutions, Facebook may be the right place for you. 
• Move Fast: Facebook always thinks one step ahead. So when it comes to innovation, going slow is just out of question, and candidates who believe the same are on the company’s checklist.
• Passion to contribute to society: Facebook wants to hire professionals who are not just looking for a hefty salary but want to fulfill a purpose and impact people's lives positively. 

Keeping the above points in mind will help you frame your answers to Facebook interview questions well and come across as the right fit for the company irrespective of the job position. We hope this article helped you get some idea regarding preparing for the Facebook job interview. For more informative articles, stay tuned to Unstop.

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