This book is very unusual, but in a good way. Subjects and problems are chosen very creatively, hard or even unsolved ones are very common and many topics are usually not covered by problem solving books, such as mathematical software, Minkowsky geometry, etc.
The book is divided into 13 chapters, with myriad problems froam a large range of difficulty. Each chapter accompanies really nice references also. Here are a few things explained through the book:
Computer-aid problem solving "Cryptarithms" Problem solving techniques (particular cases, divide and conquer, patterns, simplify the problem, etc) Chapter 2 and 3 are full of nice ideas on how to deal with calculations and inequalities (farey sequences, excellent approximations,logs, etc) Proof by contradiction (self contradiction is not acceptable) Taxicab geometry, Minkowsky geometry Techniques to solve Magic Squares Cyclic numbers Game of Nim
This book certainly made me curious to read others from Shirali, given the high level of originality of this one.