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

Example Input: Where to start I have had this for 10 years and it is still ticking that alone is a tesament to how well the thing works. Over that ten years It has traveled with me to over a third of the world. This is to include half a tour in Iraq. It has been dropped and has been trough airport security more times than most people. Because of this I have never had a reason to buy an Ipod. And to be honest for music I would rather use this. Only reason that I own anything like an Ipod is that its my Iphone. So I think that the Xtra is by far the one of the best mp3 player made.
Example Output: Positive

Example Input: 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.
Example Output: Negative

Example Input: I like the book Castle In the Attic because it was very adventurous. My favorite part in the book was when Mrs.Philips gave William a gift. Do you know what the gift was? Can you figure out what it is? I recommend this book because Castle In the Attic is a very exciting novel to read.
Example Output:
Positive