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

Example Input: After repeated washings, it still smelled like a toxic plastic and who wants to put toxic plastic inside their body. Also, it didn't do the job. So I wasted my money and had to throw it away.
Example Output: Negative

Example Input: If you are not in really good shape this is a great product to get ready for P90X. It does get kind of boring because you are doing the same workouts every other day, but they do work. It is only about 30 mins but it is amazing how well it works.
Example Output: Positive

Example Input: This book was listed as used but was in perfect condition. Even after paying for express shipping we saved over $120 from the bookstore cost.Thanks Amazon!
Example Output:
Positive