I was scheduled a phone interview after introduced by a staffing firm. With simple introduction , I was told to introduce my work and my experience. I then was told to do a coding question after 10 mins. I came out a feasible solution idea very quickly. I asked the interviewer could I think further to find a optimal solution for the problem but instead she told me to write down the lengthy codes first to solve problem. I did as being requested and walk her through the logic step by step and tell her the computation complexity. The process took me about 20 mins. I then was asked to provide a better solution. I spent another 5 mins to interact with the interviewer and present her a better solution idea. She seems understand the idea and agree with the better solution but ask me again to write down the better solution codes. I quickly refactor my old codes and rewrite some major logics. This process took me another 8 mins or so. Then, I invited her to review the refactored codes again and I could walk her through the logic again in case she wants to know the details. She told me time is up because the whole interview is supposed to be 45 mins and she wants to leave 3 or 4 mins to ask her some questions. The funny part came up I realized I probably made a logic mistake on refactoring one part of my old codes. But I could not make the change since we were going to the questions and answers session. Now think back to the process, it makes me feel this is like a set up process. If she wants the best solution, then we should discuss the idea first and find out the best idea. Then implements it into codes. The whole process the interviewer is not very helpful or involved except asking and checking some minor details on the first feasible solution.