Applied online, finished online assessment and got first round of interview. A hiring manager was late for 15 min. He asked some general questions regarding past experience. When I was answering , he seems pretty quiet and not very responsive. After half of the interview time, a LC hard question was given, with only a title but without description. I wasn't clear of what it asked all along, he seems lazy to further explain. I finished half of the question, then time is up. I need to write all the test cases and class of TreeNode from scratch. It's impossible to finish the code of this difficulty, test the cases within only 20 min without having completed similar question before (imagine testing binary tree questions, you need to insert the tree nodes yourself). I don't understand what is the point of a hard leetcode question without enough explaination. I expected lots of questions regarding Java/Spring. I feel like he doesn't care at all, just picking a random hard question to filter out people not practicing hard LC questions. No questions asked regarding Java framework or Database, maybe they really need someone good at solving Leetcode questions, which is a fundemental part of future work and Software Engineering for them after all! Rejection letter arrives few hours after the interview.