Horrible experience. Out of all the interviews I had in my life, this is by far the worst experience ever because the interviewer is SO DISREPECTFUL. 1) First, the interviewer speaks terrible English and he gets frustrated when I ask for clarifications. He did not clarify the question even when I explicitly asked him for constraints, which turned his original problem into one that is a lot harder. 2) I solved the first question easily, and then he asked me a hard level LC question without clarifying it. He stays silent almost throughout the entire interview and gets extremely impatient when I ask questions. I always try to learn something from my interview, and what I learned from this experience is that crazy people also interview candidates.