It took a week to get hold of the recruiter until he finally wrote a one-liner email to schedule an initial phone chat. The following week, I had a talk with the recruiter, who scheduled a phone screen interview.

The judgment day came, and I was ready to sling some swords. The interviewer was 10 minutes late. I was really disappointed by the quality of the questions. Freaking Fibonacci. The first program I ever wrote as a programmer.

Yes, for a senior developer position, I was asked to implement a program that returns the sum of Fibonacci numbers in C#. I wrote the program in 5 minutes, which confused the recruiter somehow. So I changed the program and wrote it in a different way. He told me it was still wrong. I explained the working step by step and politely asked him to compile and run it (we were using HackerRank).

He couldn't figure out how to run it. So I made a quick fiddle on DotNetFiddle and DM'd him a link. He could clearly see how both my approaches were working fine. He argued my program's time complexity was O(n²); I proved it was O(n). Then he argued the space complexity was more and that he had a better solution. As you can see, we had already spent a lot of time on stupid things. I really wished he had asked me some quality questions and moved on, for God's sake, from Fibonacci.

I was really aggravated by the interviewer's inexperience and was ready to pack my bags for Pisa to find Fibonacci's grave and vandalize it.

I provided him a method that didn't work due to some typo. He purged the program, provided his solution, disregarding 4 different O(n) solutions. Cool. We left on good terms; he thanked me for showing DotNetFiddle and sent me a rejection letter the following week.

When people say these companies want monkeys to work for them (based on other interview reviews), they are right, except they are wrong with the animal analogy. They want donkeys to work for them who listen blindly and give birth to their sterile, hinny programs.

Cumulative sum of Fibonacci series