Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Impossible to solve?

I have bought this toy a while ago and still have not solved it. Apparently there are a lot of ways to solve this, yet I still have to find one way. Every now and then I get really frustrated, but I cannot stop myself from trying to solve this again. As for kids using this as a toy: I can see how it's entertaining for a while, but kids can also get terribly discouraged. My son, then 9 years old, has tried to solve this for about an hour, and never touched it again after that.