Booking.com Software Developer Willing to Learn Perl interview questions

I've expected to hear questions about data structures, algorithms, problem solving tasks, maybe tasks to fuckyourbrain, or another simple math problems etc. They proposed me to code a function in pseudocode to get a short version of a description. But to keep whole words in a sentence and do not cut them. After that they asked me questions about each line and proposed to improve my 2 lines of code to get it faster. They tried to tip me using caching there. Anyway looks like it was enough for them to understand something about me that caused to reject my application with general explanation that I do not have deep knowledge in area they needed.