The problems with this book are:
(1) The authors failed to explain the math involved in neither rigor nor
intuitive way. The authors frequently try to introduce algorithms before
explaining the concepts or definition.
(2) The book is a mixture of number theory, linear algebra, cryptography, mixed
almost randomly, without proper dependency logic. Neither cryptography algorithm,
no number theory or linear algebra concepts involved are explained clearly.
(3) It is more like a notebook taken by a student. It appears that the authors
simply submit the lecture notes for publication, none efforts were made to
turn a lecture notes to a published book.
Readers are not their students, they do not have access to the authors.
It appears to me that this is the only explaination, since I hate to doubt the
authors capability in writing a textbook in this field. I simply can not imagine
a competent professor in his field writing such a confusing textbook.
I hate to spend my time in writing this note, but this book wasted too much my time,
I just hope others will be lucky that I am. My knowledge in both math and CS are above
Master degree level.