Parity

The book is devoted to the tasks related to the concept of partiality. It includes the development of four classes of a mathematical circle with detailed examples of various complexity and methodological instructions for the teacher.
A large list of additional problems with solutions is given. Most of the tasks considered in the book are "classic" for this section of mathematics. For ease of use, the final part of the book is made in the form of handouts.
The book is addressed to school teachers of mathematics and leaders of mathematical circles. We hope that she will be interesting to schoolchildren and their parents, as well as all fans of mathematics.
7th edition, stereotypical