I applied through an employee referral. The process took 3 weeks. I interviewed at Meta in Jan 2015
Interview
I was referred to Facebook by a friend who works there and was contacted by a member of HR about a week later. We set up a date for a 45-minute technical phone interview which was to be held a week and a half later.
For the actual interview, I was first asked a couple of generic questions about myself and Facebook before moving on to the technical questions. There were two programming questions.
For the first question, I first described what my algorithm would be, then discussed time and space complexity before finally implementing it. My interviewer didn't have anything to say about my answer and we simply moved on.
I took the same basic approach to the second question; described my algorithm, discussed space/time complexity, and then implemented it. However, after discussing the space and time complexity for my potential solution, my interviewer asked me if I saw any draw-backs to my algorithm. I told him that it used a lot of extra space, and he asked if I could think of a more efficient (space-wise) solution. I thought about it for awhile, but unfortunately blanked out. He then suggested I just go ahead and implement my algorithm.
The last 5 or so minutes of the 45 minute interview were devoted to me asking questions. I asked a few, and the interview was over.
I received a generic rejection email 3 days later.
Given "data", "from", and "to" fields, replaces all occurrences of the characters in the "from" field in the "data" field, with their counterparts in the "to" field.
Example:
Input:
Data: "Hello World"
From: "lod"
To: "xpf"
Output:
"Hexxp Wprxf"
Took about a month from start to finish, which felt longer than I expected. After a couple of initial phone screenings, I faced a challenging technical round focused on system design. It was during this round that I was asked to describe overcoming a major career challenge. Interestingly, I had just reviewed a similar framework on PracHub, which helped me articulate my thoughts clearly. Overall, I appreciated the depth of the process and ended up accepting the offer.
Interview questions [1]
Question 1
Describe Overcoming a Major Challenge in Your Career
The entire process usually takes 3–8 weeks, depending on scheduling and the specific role. Coding interviews heavily emphasize common DSA topics such as arrays, strings, trees, graphs, BFS/DFS, heaps, hash maps, and dynamic programming. System design becomes increasingly important for E4+ positions.
Interview questions [1]
Question 1
Given an array of integers and a target value, return the indices of two numbers that add up to the target
Unexpectedly, the first question in the technical round felt familiar. It was about finding a subset of strings with unique character concatenation — same problem I had worked through on PracHub a few days earlier. The interview included a recruiter screen followed by a rigorous pair of technical interviews where I tackled data structures and algorithms alongside system design concepts. After successfully answering a few more challenging DSA questions, I received an offer. The entire experience was intense but ultimately rewarding, and I happily accepted the position.
Interview questions [1]
Question 1
Given an array of strings, pick a subset whose concatenation contains no duplicate characters, and return the maximum possible length of that concatenation.
