Meta (Facebook) Software Engineer Interview Questions

Aymen D. - "It would have been more interesting to focus on the system design rather than the Trie DS, Interviewee could have just mentioned the Trie and passed to things more important. Interviewee should have focused on the factors on which he wants to scale the API servers, popularity of the query parts ? region may be ? A hash of many factors ? Caches should have definitely be discussed, Cache eviction policies, Cache invalidation managements... Interviewee should have mentioned which kind of API pro"See full answer

Kanishvaran P. - "class Solution { public boolean isValid(String s) { // Time Complexity and Space complexity will be O(n) Stack stack=new Stack(); for(char c:s.toCharArray()){ if(c=='('){ stack.push(')'); } else if(c=='{'){ stack.push('}'); } else if(c=='['){ stack.push(']'); } else if(stack.pop()!=c){ return false; } } return stack.isEmpty(); } }"See full answer

Yugaank K. - "A recursive backtracking solution in python. def changeSigns(nums: List[int], S: int) -> int: res = [] n = len(nums) def backtrack(index, curr, arr): if curr == S and len(arr) == n: res.append(arr[:]) return if index >= len(nums): return for i in range(index, n): add +ve number arr.append(nums[i]) backtrack(i+1, curr + nums[i], arr) arr.pop() "See full answer

Pathworks P. - "To answer this, I will focus my efforts on explaining the most common type of API used in most modern software development applications - the REST API. For the purpose of simplicity, I will also keep the topics of Authorization and Authentication out of the mix. In essence, an API is a group of logic that takes in a specific set of inputs and responds with a specific set of outputs. This is analogous to going to a drive-thru and placing an order for a meal. When you give an API a bunch of"See full answer

Faraz A. - "Scoped out problem constraints - how much data to download, how many computers, and how much time, how you can be detected (decentralized load). Designed a web crawler."See full answer

Tiago R. - "function isValid(s) { const stack = []; for (let i=0; i < s.length; i++) { const char = s.charAt(i); if (['(', '{', '['].includes(char)) { stack.push(char); } else { const top = stack.pop(); if ((char === ')' && top !== '(') || (char === '}' && top !== '{') || (char === ']' && top !== '[')) { return false; } } } return stack.length === 0"See full answer

Adam M. - "This is a great question! If you don't mind, I'd love to list 3 strengths and weaknesses then dive a little deeper on one of each of them. I think my three greatest strengths are: Empathy Openness to feedback Drive And three weaknesses I have been working to strengthen are: Sometimes my desire to achieve can put me at risk of overcommitting Communicating status to the right stakeholders at the appropriate time Creating detailed and strategic lists of priorities so I can meet th"See full answer

דניאל ר. - "Implemented a recursive function which returns the length of the list so far. when the returned value equals k + 1 , assign current.next = current.next.next. If I made it back to the head return root.next as the new head of the linked list."See full answer

Amparo L. - "One time at Lifetime Fitness 2019, One student was throwing a lot of towels in the counter which made things very disorganized, then I made a compromise with my coworker to put 2 towels at a time and then it worked well because it made the workspace very organized."See full answer

Avon T. - "Initialize left pointer: Set a left pointer left to 0. Iterate through the array: Iterate through the array from left to right. If the current element is not 0, swap it with the element at the left pointer and increment left. Time complexity: O(n). The loop iterates through the entire array once, making it linear time. Space complexity: O(1). The algorithm operates in-place, modifying the input array directly without using additional data structures. "See full answer

Srini K. - "performance issues and sudden spikes on input requests by scaling techniques and optimization."See full answer

Khushbu R. - "General Approach (using Max-Heap) Use a max-heap (priority queue) of size k. For each point: Compute the distance to P. Push it into the heap. If heap size > k, remove the farthest point. The heap will contain the k closest points to P. import java.util.*; public class KClosestPoints { static class Point { int x, y; public Point(int x, int y) { this.x = x; this.y = y; } // Euclidean distance squared (no need to take square root) p"See full answer

Scott S. - " The Situation A few months ago, our trading platform started experiencing significant latency issues during peak trading hours. This latency was affecting our ability to process real-time market data and execute trades efficiently, potentially leading to substantial financial losses and missed opportunities. Identifying the Problem The first step was to identify the root cause of the latency. I organized a team meeting with our data engineers, DevOps, and network specialists to gather"See full answer

Kurt K. - "Why skip defining the data model? Or did I just miss it?"See full answer

Push S. - "STAR story weaved around the project 0 to 1 execution with all the technical tradeoffs, issues, and success metrics involved."See full answer

Aswath B. - "basic drew the diagram"See full answer

Rjj - "I tried solving this question and here is the recorded video for the entire solution - https://youtu.be/G_LIbTp58XA Feel free to comment here or on the video for further discussion."See full answer

Dinesh K. - "i dont know"See full answer

Shuchi A. - "A few months ago I joined a micro-services platform engineering team as their manager, at that time my team was struggling to deliver towards an upcoming production deadline for a customer facing product. Production date had been moved 5 times already and there were about 40% of product features which were remaining to be tested and signed off to move to production . I was made responsible to deliver the release of this product within the deadline and turnaround the software delivery throughput."See full answer