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

Example Input: I purchased this MP3 player as a Christmas gift for our daughter only to find out on Christmas Day that is not compatible without our computer despite every update available. While we could see the preloaded video and it is very clear and bright, we were never able to upload any music. My husband (who is computer wizard) spent 12 hours trying to get this thing to work, but without any success. Next time we'll buy an IPod.
Example Output: Negative

Example Input: works great! so easy to use with "click to DVD" software that came on my Sony Vaio PC. love it! I can finally have my home videos put on DVD easily, in about an hour or so.
Example Output: Positive

Example Input: This is a very good description of Luftwaffe Operations on the Eastern Front. It has good background information speciffically about the economic side of it. Decisions made based on oil supply's rather than military objectives. Very interesting material.The only bad thing about this book is that the editing comes across as very sloppy. German names are often misspelled or incorrect. It is not Manstein, but von Manstein, not Bock, but von Bock, not Kluge, but von Kluge.Also it is not Count von Sponneck but Graf von Sponneck. If you overlook those issues, it is a very good book
Example Output:
Positive