Interviewers who ask LC hards

It's a way of asserting their own intelligence even though that same jack ass had to read the leetcode solution and was stuck on it for 3 hours.

It means they have already decided not to hire this person and just want to assert their superiority and make them feel like nobody for the whole 45 -60 min interview session so that he/she could feed their insecurities and feel little bit better about themselves.

Why is LRU cache problem a fake hard? What difficulty do you consider it: easy or medium.

We don't look for optimal solutions ever. From LRU to 2dimensional DP, all we assess is how you can think about a problem, how you can take guidance from us to achieve a solution. Even if you knew the answer, I would at least 5 "whys ?" (:P) to see your level of understanding. It's a small window to see how you would work in a team environment. (At least, that's how Amazon works)

"Here at FANG, trapping rainwater is critical for our business"

I was asked wildcard/regex matching in a phone interview with some fintech firm.

Let’s file a petition to change the difficulty label of LRU

Haven't interviewed at G yet, but at my previous company I always look for how you approach the problem. I usually expect a clean, readable brute force solution with a good explanation for its time/memory complexity and why it won't work for the bigger case and see how you try and approach the harder case. What things you think are difficult, etc.

When interviewers are asking these kind of questions, they should be aware of the fact that it’s highly impossible to solve in a 45 min interview. Most of them would consider a verbal solution as meeting the bar whereas implementing partial solution as raising the bar in which they give you a ‘strong hire’.

I've administered around 300 interviews to date at Amazon. Tried all sorts of questions from my own to LC easys to LC hards. I have learned that when asking a DP leetcode hard question, there two types of people. 1) I already know the solution or 2) I stare at the white board for 1 hour. When I hear people say "I'm looking for how they approach the problem" they are full of shit. What usually happens is as an interviewer you start feeding the answer. Some can take your suggestions and get code on board. Others cant. So did you administer an effective interview? I argue you did not. An effective interview should test problem solving, ability to write code and algorithm/data structure knowledge. A question like "implement a hash table" gets way more of those data points than some of these LC hards.