Given the task definition and input, reply with output. In this task, you're given a review from Amazon. Your task is to generate a rating for the product on a scale of 1-5 based on the review. The rating means 1: extremely poor, 2: poor, 3: neutral, 4: good, 5: extremely good.

This stuff works amazing on my hair. I have "some" gray and that's fine and was looking for something to comb through the sides where my grey is really bad. My hair grows fast and I've used this 3 times now (about every month/half for my hair on the sides and other areas using the included comb. By the time I'm done combing, it's ready and died perfectly... Fast and easy.
5