Very first interview was live leetcode-like problem solving excercise. The problem is that idea behind the solution is quite unique and difficult to approach, Even despite I have solved several hundreds leetcode-like problems. Like "you have to know how to solve this or should have seen it before by any chance (and you most likely have not)". Optimizations are quite tricky too, especially the optimal solution. Quoting the interviewer "the optimal solution pattern is X, but you most likely have not seen this before". Indeed... I am disapproving the interview because I don't see a value of such problem solving challenge and not sure how it helps estimate candidates. Since this was the first and only interview, my all skills related to the role and past experience are simply neglected by unrelated problem solving task.