Meta Software Developer interview questions

Did a phone screen with them. The interviewer gave me a task which I already knew the solution for at first (find two elements in an integer array which sum up to a given number). When I pointed out that I know the solution to the problem, he gave me another one: to determine if a sequence of numbers is monotonic (i.e. ascending or non-descending). The interviewer didn't seem to understand the difference between non-decreasing and ascending sequences and it took a while to figure out the exact specification for the problem. The interviewer expected a straightforward solution which compares elements pairwise, but I came up with a more elegant one, which is based on calculating the pairwise difference and would require only a single array traversal. The interviewer didn't understand my solution and told me that he haven't seen this solution before and it wasn't the solution he was excepting. Eventually, he couldn't come up with an example where my code wouldn't work or a flaw in my reasoning. I've got feedback that my solution wasn't the one the interview was expecting and therefore rejected.

Single on campus interview with two simple questions. Went to University Day in Menlo Park a few weeks later for two technical and one behavioral interview. Everything seemed to go okay for technical interviews, but caved under pressure for coding exercise thrown in at the end of the behavioral interview. Received rejection email less than a week after.