Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Excellent!

The foundations outlined in the first three parts of the book are strengthened with a practical language and I sum up. I received the book few days ago and it impressed me the form in which arrives to the reader, in the personal thing the knowledge of the book they will help me to strengthen my knowledge in cryptography. Maybe with images of digital certificates the book would have bigger back, although for the year of edition it is understandable.