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

Example Input: As well as a trilogy that is as far-reaching as it is set in a far-distant time with characters and galactic backdrop unrivaled by any other book. Definitely one of the great science-fiction classics just like "Stranger in a Strange Land", "Childhood's End", along with modern-day cyberpunk like "Neuromancer", "Count Zero", "Prey", "Cryptonomicon", "Snow Crash", "Darkeye: Cyber-Hunter", etc.
Example Output: Positive

Example Input: I really enjoyed this book!I couldn't put it down after the first page which compares Marshall, "An average North American Male" ... "plump and balding", to his caged pet bird - "Both had lived three fourths of their expected life span and had another fourth of life to go, if they were lucky".This sets the tone for the novel which is a thought provoking story written with wit and intelligence.I should note, however, this is not and it is a book about the character Marshall Hollenzer. It is really a book about people - the choices they make and/or the fate bestowed upon them - and journeys - both physical and spiritual.This novel is thought provoking, entertaining, and enlightening.I recommend buying at least two copies - this is the type of book that you will want to share with people you know.
Example Output: Positive

Example Input: We received the Intex Pillow Rest Twin Airbed with Built-in Electric Pump on September 10th 2008. It is for our 8 year old daughter who has joint pain due to a genetic disorder. Her doctor recommends an air bed to relieve the pressure on her joints caused by a "traditional" mattress. The first 2 months it worked great. She was sleeping better and woke up in less pain. The next few months we had to pump it up every other day, but she still was in less pain. Now today, April 11th 2009, just 7 months later she can't even sleep on it. Within 3 hours the bed is almost completely flat. Our daughter is now sleeping on couch cushions until we can find a new bed. Don't waste your money on this bed! Find ANY OTHER airbed, you'll be much happier.
Example Output:
Negative