Arcesium Interview Experience for SDE | Off-Campus (6 Months Experienced)

Arcesium Interview Experience for SDE | Off-Campus (6 Months Experienced)
Total 4 Rounds
Hacker rank Assessment  
2 x Technical Interviews 
HR Round
Round 1 (Hacker Rank Assessment): 3 Problems related to Graphs, Ad Hoc Maths. Managed to solve all 3 problems.
Round 2 (Technical Interview I): This round was taken by a Sr. Software Engineer.
Brief Introduction
Describe the Favourite Project that you have worked on. (5-10 mins) Then he cross-questioned some decisions made along the way and why they were made.
DSA Problem – Tell if a given array of numbers is strictly increasing, strictly decreasing, increasing then decreasing, or decreasing then increasing.
I gave the brute force approach first. He wanted me to optimize it. I gave a binary search-based (O(log n)) approach. He asked me to code it.
He then asked me to further optimize it and give O(1) approach. I had no idea how to do it in O(1), but after thinking a lot, I told him that we’ll need to guarantee that either of these four cases occurs, only then we can compare the first two and last two elements to determine the order of the array. If the array is neither of these 4 cases, then this approach won’t work.
What is process?
What is a thread?
How is a process different from a thread?
Does a parent process share memory with its thread?
I asked them 3 questions in the end regarding the work culture and the role.
Round 3 (Technical Interview II): Taken by 2 Sr. SDEs.
Project Description and basic questions regarding decisions made along the way
DSA – Rot all Oranges (Optimised Approach + Code) on Hackerrank Code Share Page
Real-life uses of LRU and MRU
What is an interface?
How are interfaces implemented in C++?
I asked them 3 questions in the end regarding the work culture and the role.
Round 4 (HR Round): Questions on aspirations and why I want to leave my current company, why I want to join Arcesium, and Salary expectations.
I asked her 2 questions in the end regarding the role.