Meta Software Engineer interview questions

Did three rounds of interviews. First round: design a system to detect homeworking copying, which means input two strings and a integer K, if there is a common substring of them have length larger than K, return true, else return false. Second round: nearly all behavior questions. In the last five minutes, asked me to code up a linked list reverse function Third round: build a dictionary trie and implement search function, mainly focusing on the OO designing pattern.