EPAM Systems interview questions

Interviewer was quite tired, like he didn't even want to conduct anything. Questions were initially coming with theoretical perspective, i.e. do you know this?, do you know that? explain please.. but as we were reaching the deadline it switched to more system design-ish approach, where the interviewer started to ask quite high-level questions; the problem for me was that such a sudden switch between perspectives - in less than half an hour - is too much.. after all that, we were also allowed to exceed a bit our interview process to conduct a practical examination of writing a LinkedList, as in Java; besides the fact that interviewer surely didn't grasp my idea of Nodes connection, as opposed to Array-alike memory usage, and as I believe was really expecting from me real Java's LinkedList implementation, the interviewer also wasn't really saying much about time boundaries, except the fact that we were running out of predefined time-slot, which felt like he was either giving me "enough" time for the Java like realization, or he was silently seeking out a polite way to end everything faster. May be someone of course will do it easily - switch between perspectives, know JDK's implementation details, and ask the right timing questions, but still the highest grade will be somewhere around a Senior grade, but compensation will be much less than the market mean one