The initial contact was a phone call from HR, followed by an online coding assessment via HackerRank. This part was very simple.

I was then contacted by the lead engineer for another technical phone screen and was invited onsite for an interview. The on-site interview consisted of four people and lasted one hour.

It included:

• One behavioral interview
• Two whiteboarding interviews
• One other non-whiteboarding technical interview

The whiteboarding exercises were of average difficulty.

My negative experience was that not once during these interviews did the interviewers point out any specifics in the code I was writing. They were observers, not engaged in a dialogue.

The single vague reason for my rejection was that they needed a person with more experience. However, I couldn't even get an answer as to whether that meant years of experience or if there were certain skills I could improve on.

I was encouraged to apply for other jobs at the company, but without a fair evaluation of my strengths and weaknesses from these observers, this is a waste of time.

Write a function to count the most frequently used letter in a string.