There are 3 main questions in code test, but the progress that I go here is only past the first part, and in code test. There are 3 different difficulty question, the first one is easy just use split and I write a dictionary to convert like list to string, and sum the number if there are two same string name, so hash map works. The 2 one is like deal with number like odd even, I can't remember clearly but it is not even harder than the first question even it is a medium question, The third one is really hard, I try a lot of time to figure out it, its like encrypt and decode the input.