Hashedin Interview Experience for Software Engineer (On-Campus 2021)

Round 1: There were 3 questions in round 1 and one was very basic(array/string), one last moderate(linked list/tree) and the last one was hard(graph).

I could solve 2 questions out of three and manage it to shortlist for further rounds. There was a total of 130 students from CS, IT, ECE.

Round 2: For the interview, 28 students were shortlisted and the interview process start after 1 hr when the candidate list shared. 

It takes around 50-55 minutes and the interviewer was very polite and friendly. 

Questions he asked are as follows:

1. How many bits will a number n required to represent a binary number converted from decimal? I solve simply by using a while loop, he asked me to solve in O(1). And gave me hint to solve using log. (using time complexity) 
2. How to find out the missing number from an array of n elements that have elements from 1 to n+1. Again I solved it using a loop. He asked for another approach. I used sorting and binary search. He asked again for another approach and gave hint after some time. I used AP to find out the correct answer.
3. To find out the missing numbers from an array of unsorted elements which will have all paired elements after inserting this missing number. (Having 2 same elements or numbers and one is single. I solved it with O(n*n)  and then O(nlogn). Then he asked me to solve using xor operator 
4. He asked one question from the linked list I just forget the question but here he asked to find its space complexity, but I couldn’t find it correctly. He then told me how to solve that problem using space complexity.
5. There was one another question related to strings and that was too easy. I told him three approaches for the same question as I was comfortable in strings. At last, he asked, Do you have any questions for me? Although I could ask him better questions. 

Note: It was easy but the time and space complexity of the program will decide your result.

Overall it was a great experience, and I was expecting another round of interviews, but it doesn’t happen. 12 were shortlisted for the next round.

I would like to suggest not don’t commit the same mistakes. Should go through interview problems on GeeksforGeeks. Should be able to find space complexity and should learn to write the most optimized solution. Tell him properly how you are going to solve as he asked it before you start writing solution.