Amazon Lab126 QA Manager interview questions

Entire process took almost a month. The interview process was very organized. First had a phone interview with hiring manager. Later got invitation for in-person interview. Went to Sunnyvale office for 4 hour interview. The interviewers were pleasant and asked some repeated questions. I was asked to write a piece of code on the white board. After I completed the code, the interviewer(Development manager) mentioned that my approach was not the best one. I was curious to know the other alternative approach. After he explained his approach, I realized that mine was better way to handle the problem. This is where I was disappointed - The interviewer assumed that I will not be able to solve the problem and simply told that there is a better approach to solve the problem. I was very polite and explained why my method works efficiently too. Overall I thought my interview went well. But looks like they picked internal candidate for the post.