We'll have to agree to disagree. I think implement a string builder is a GREAT interview question. The point is to have a discussion. Why? What are the benefit

We'll have to agree to disagree. I think implement a string builder is a GREAT interview question. The point is to have a discussion. Why? What are the benefits of a string builder? When is it necessary? What performance characteristics should it have. What kind of questions do you ask, what kind of edge cases do you consider? It's an interview - if you are not sure why the interviewer is asking you to re implement a standard library, ASK. This is not unusual for Amazon - most tech companies these days ask these kinds of questions