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

Example Input: This set of assorted short tracks is hard to avoid if you want to create a track layout of even an intermidiate size. The male-male and female-female pieces will provide a dramatic increase in the number of layouts possible as you can now overcome the problem of curves returning to the starting position.This is a must-have for any Brio enthusiast.
Example Output: Positive

Example Input: What am I reviewing here... this gizmo or the supplier, Eforcity? I never received this product after my order! After waiting and waiting I contacted Eforcity several times -- no reply. After a nasty letter from me Eforcity'r reply feigned lacking information about my mailing address!What a cop-out.I told them I would not pay for it, so Eforcity said they'd give me a refund, which has not come to me yet. I bought another product to replace this from Amazon which arrived quickly from Amazon.
Example Output: Negative

Example Input: I got this product in April and exactly two months later it said my subscription had expired and I needed to renew in order to keep receiving updates for antivirus protection.I wrote to the company and a week later they sent me a reply. The reply was to go to their update center and to renew. I sure wasn't going to pay again for something I only had for two months and its suppose to last for a year.I'll be going back to my trusted Norton Antivirus, it may be slow but at least I only have to buy it once a year.
Example Output:
Negative