Given reviews from Amazon, classify those review based on their content into two classes: Negative or Positive.

Q: This would have been a very short book if all of the racism and sexuality were to be removed. I read it for an Appalachian Literature class, and I felt this book was so racey that I couldn't enjoy reading it. The vulgarity in it is also not necessary, and I feel that it should not be called literature because of this.

A: Negative
****
Q: I was very excited to buy this scanner and was pleased with its size and weight. However, if you have a Vista operating system, like I do, IT WILL NOT WORK! The company told me that they stopped selling this product over a year ago and there are no driver updates available for this product. If you have an older computer and an older operating system this product might work for you. But as for me it was a waste of money!

A: Negative
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Q: If you have the patience to read the first 100 pages you'll not be able to put this book aside.The first time I read this book I was 14. I've probably read it a dozen times by now. The plot is extremely good. The outcomes of every event (since the group leaves Trantor) are surprising, the way the main heroes solve the problems are exciting and satisfying (to me at least). The good amount of dialogues keeps the book from becoming boring and overly descriptive.Asimov's imagination is as yet unsurpassed!

A:
Positive
****