EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book Sudoku 9 X 9   250 Puzzles 3 Numbers   Hermit  Vol  134

Download or read book Sudoku 9 X 9 250 Puzzles 3 Numbers Hermit Vol 134 written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-14 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent puzzles at the level of bronze, silver and gold. All riddles have only 1 solution. 2 puzzles per page. Balanced location of riddles. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. The numbers on the sides of the Sudoku indicate the sum of the 3 nearest digits located horizontally or vertically. No matter what figure of the playing field we take in all the cells around it (horizontally, vertically or diagonally), there should not be such a figure. This means that for any randomly taken 3x3 square, the central figure of this square occurs only once in it. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Skyscraper Puzzles   Hermit   Level Silver

Download or read book Sudoku 9 X 9 250 Skyscraper Puzzles Hermit Level Silver written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-13 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: - 250 exciting sudoku puzzle - level of the silver medalist - each Sudoku has a unique solution - tasks are conveniently located - large print - develops memory, logical thinking, helps with concentration. Sudoku is useful at any age for developing mental abilities and maintaining them in perfect condition. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. Contains key numbers located along the sides of Sudoku. It is necessary to arrange the numbers in cells; each figure indicates the number of floors in a skyscraper. Key numbers outside the cells show how many houses can be seen in the corresponding row or column, if viewed from this number. No matter what figure of the playing field we take in all the cells around it (horizontally, vertically or diagonally), there should not be such a figure. This means that for any randomly taken 3x3 square, the central figure of this square occurs only once in it. Excellent purchase for fans of Sudoku. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Skyscraper Puzzles   Hermit   Level Bronze

Download or read book Sudoku 9 X 9 250 Skyscraper Puzzles Hermit Level Bronze written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-13 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: - 250 exciting sudoku puzzle - level of the bronze medalist - each Sudoku has a unique solution - tasks are conveniently located - large print - develops memory, logical thinking, helps with concentration. Sudoku is useful at any age for developing mental abilities and maintaining them in perfect condition. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. Contains key numbers located along the sides of Sudoku. It is necessary to arrange the numbers in cells; each figure indicates the number of floors in a skyscraper. Key numbers outside the cells show how many houses can be seen in the corresponding row or column, if viewed from this number. No matter what figure of the playing field we take in all the cells around it (horizontally, vertically or diagonally), there should not be such a figure. This means that for any randomly taken 3x3 square, the central figure of this square occurs only once in it. Excellent purchase for fans of Sudoku. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Puzzles 3 Numbers   Anti   Knight  Vol  133

Download or read book Sudoku 9 X 9 250 Puzzles 3 Numbers Anti Knight Vol 133 written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-14 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent puzzles at the level of bronze, silver and gold. All riddles have only 1 solution. 2 puzzles per page. Balanced location of riddles. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. The numbers on the sides of the Sudoku indicate the sum of the 3 nearest digits located horizontally or vertically. In this Sudoku the same numbers can not "beat" each other with the chess steed. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Puzzles 3 Numbers   Central Points  Vol  131

Download or read book Sudoku 9 X 9 250 Puzzles 3 Numbers Central Points Vol 131 written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-14 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent puzzles at the level of bronze, silver and gold. All riddles have only 1 solution. 2 puzzles per page. Balanced location of riddles. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. The numbers on the sides of the Sudoku indicate the sum of the 3 nearest digits located horizontally or vertically. The central points of each of the 3 x 3 cells must not repeat numbers from 1 to 9. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Puzzles 3 Numbers   Wheel of Fire  Vol  130

Download or read book Sudoku 9 X 9 250 Puzzles 3 Numbers Wheel of Fire Vol 130 written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-14 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent puzzles at the level of bronze, silver and gold. All riddles have only 1 solution. 2 puzzles per page. Balanced location of riddles. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. The numbers on the sides of the Sudoku indicate the sum of the 3 nearest digits located horizontally or vertically. In these Sudoku there is an area in the form of fireworks (Wheel of fire) with numbers from 1 to 9. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Puzzles 3 Numbers   Octagonal Star  Vol  129

Download or read book Sudoku 9 X 9 250 Puzzles 3 Numbers Octagonal Star Vol 129 written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-14 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent puzzles at the level of bronze, silver and gold. All riddles have only 1 solution. 2 puzzles per page. Balanced location of riddles. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. The numbers on the sides of the Sudoku indicate the sum of the 3 nearest digits located horizontally or vertically. In these Sudoku, there is an area in the form of an octagonal star with numbers from 1 to 9. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Number   X   Hermit Sudoku   250 Puzzles Bronze   Silver   Gold   Vol  186

Download or read book Number X Hermit Sudoku 250 Puzzles Bronze Silver Gold Vol 186 written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-25 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 fascinating puzzles. Levels go on increasing. You can start with a bronze medalist, this is the first 80 puzzles. You can go to the champion, the gold prize - 90 extreme Sudoku. Silver puzzles are in the middle of the book. All riddles have only 1 solution. 2 puzzles per page. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide internal edges allow you to record solutions. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. No matter what figure of the playing field we take in all the cells around it (horizontally, vertically or diagonally), there should not be such a figure. This means that for any randomly taken 3x3 square, the central figure of this square occurs only once in it. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book The Algorithm Design Manual

    Book Details:
  • Author : Steven S Skiena
  • Publisher : Springer Science & Business Media
  • Release : 2009-04-05
  • ISBN : 1848000707
  • Pages : 742 pages

Download or read book The Algorithm Design Manual written by Steven S Skiena and published by Springer Science & Business Media. This book was released on 2009-04-05 with total page 742 pages. Available in PDF, EPUB and Kindle. Book excerpt: This newly expanded and updated second edition of the best-selling classic continues to take the "mystery" out of designing algorithms, and analyzing their efficacy and efficiency. Expanding on the first edition, the book now serves as the primary textbook of choice for algorithm design courses while maintaining its status as the premier practical reference guide to algorithms for programmers, researchers, and students. The reader-friendly Algorithm Design Manual provides straightforward access to combinatorial algorithms technology, stressing design over analysis. The first part, Techniques, provides accessible instruction on methods for designing and analyzing computer algorithms. The second part, Resources, is intended for browsing and reference, and comprises the catalog of algorithmic resources, implementations and an extensive bibliography. NEW to the second edition: • Doubles the tutorial material and exercises over the first edition • Provides full online support for lecturers, and a completely updated and improved website component with lecture slides, audio and video • Contains a unique catalog identifying the 75 algorithmic problems that arise most often in practice, leading the reader down the right path to solve them • Includes several NEW "war stories" relating experiences from real-world applications • Provides up-to-date links leading to the very best algorithm implementations available in C, C++, and Java

Book Sudoku 9 X 9   250 Hermit Puzzles   Level Bronze

Download or read book Sudoku 9 X 9 250 Hermit Puzzles Level Bronze written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-02-25 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent, proven variations Sudoku bronze. Balanced location of riddles. 2 puzzles on each page. Each Sudoku has a unique solution. A wide internal space will allow you to record many of your moves in solving a problem. Your mental abilities will be in perfect condition. A great gift for connoisseurs of Sudoku. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. No matter what figure of the playing field we take in all the cells around it (horizontally, vertically or diagonally), there should not be such a figure. This means that for any randomly taken 3x3 square, the central figure of this square occurs only once in it. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Skyscraper   Anti   Knight Puzzles   Level Silver

Download or read book Sudoku 9 X 9 250 Skyscraper Anti Knight Puzzles Level Silver written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-13 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: - 250 exciting sudoku puzzle - level of the silver medalist - each Sudoku has a unique solution - tasks are conveniently located - large print - develops memory, logical thinking, helps with concentration. Sudoku is useful at any age for developing mental abilities and maintaining them in perfect condition. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. Contains key numbers located along the sides of Sudoku. It is necessary to arrange the numbers in cells; each figure indicates the number of floors in a skyscraper. Key numbers outside the cells show how many houses can be seen in the corresponding row or column, if viewed from this number. In this Sudoku the same numbers can not "beat" each other with the chess steed. Excellent purchase for fans of Sudoku. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Puzzles 3 Numbers   Anti   Diagonal  Vol  135

Download or read book Sudoku 9 X 9 250 Puzzles 3 Numbers Anti Diagonal Vol 135 written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-14 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent puzzles at the level of bronze, silver and gold. All riddles have only 1 solution. 2 puzzles per page. Balanced location of riddles. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. The numbers on the sides of the Sudoku indicate the sum of the 3 nearest digits located horizontally or vertically. In Sudoku Anti Diagonal each diagonal of the square contains no more than three different digits. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Skyscraper   Central Points Puzzles   Level Gold

Download or read book Sudoku 9 X 9 250 Skyscraper Central Points Puzzles Level Gold written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-12 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: - 250 exciting sudoku puzzle - level of the gold medalist - each Sudoku has a unique solution - tasks are conveniently located - large print - develops memory, logical thinking, helps with concentration. Sudoku is useful at any age for developing mental abilities and maintaining them in perfect condition. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. Contains key numbers located along the sides of Sudoku. It is necessary to arrange the numbers in cells; each figure indicates the number of floors in a skyscraper. Key numbers outside the cells show how many houses can be seen in the corresponding row or column, if viewed from this number. The central points of each of the 3 x 3 cells must not repeat numbers from 1 to 9. Excellent purchase for fans of Sudoku. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Puzzles 3 Numbers   Windowdoku  Vol  132

Download or read book Sudoku 9 X 9 250 Puzzles 3 Numbers Windowdoku Vol 132 written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03-14 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent puzzles at the level of bronze, silver and gold. All riddles have only 1 solution. 2 puzzles per page. Balanced location of riddles. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. The numbers on the sides of the Sudoku indicate the sum of the 3 nearest digits located horizontally or vertically. This Sudoku has 4 additional windows 3 x 3 in which the numbers from 1 to 9 are not repeated. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Killer Sudoku 9 X 9   250 Hermit Puzzles   Level Silver

Download or read book Killer Sudoku 9 X 9 250 Hermit Puzzles Level Silver written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent puzzles at the level of silver. All riddles have only 1 solution. 2 puzzles per page. Balanced location of riddles. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. The sum of all numbers in the marked section must correspond to the number written in the corner of this section. No matter what figure of the playing field we take in all the cells around it (horizontally, vertically or diagonally), there should not be such a figure. This means that for any randomly taken 3x3 square, the central figure of this square occurs only once in it. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Sudoku 9 X 9   250 Hermit Puzzles   Level Gold

Download or read book Sudoku 9 X 9 250 Hermit Puzzles Level Gold written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-02-25 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent, proven variations Sudoku gold. Balanced location of riddles. 2 puzzles on each page. Each Sudoku has a unique solution. A wide internal space will allow you to record many of your moves in solving a problem. Your mental abilities will be in perfect condition. A great gift for connoisseurs of Sudoku. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. No matter what figure of the playing field we take in all the cells around it (horizontally, vertically or diagonally), there should not be such a figure. This means that for any randomly taken 3x3 square, the central figure of this square occurs only once in it. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko

Book Killer Sudoku 9 X 9   250 Hermit Puzzles   Level Gold

Download or read book Killer Sudoku 9 X 9 250 Hermit Puzzles Level Gold written by Andrii Pitenko and published by Createspace Independent Publishing Platform. This book was released on 2018-03 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: 250 excellent puzzles at the level of gold. All riddles have only 1 solution. 2 puzzles per page. Balanced location of riddles. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 9x9, separated by smaller rectangles of 3x3 cells. It is necessary to fill empty cells with numbers from 1 to 9, each of the digits should appear only once in each line of the 9x9 square, 9x9 column and 3x3 rectangle. The sum of all numbers in the marked section must correspond to the number written in the corner of this section. No matter what figure of the playing field we take in all the cells around it (horizontally, vertically or diagonally), there should not be such a figure. This means that for any randomly taken 3x3 square, the central figure of this square occurs only once in it. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. Sudoku will provide you with relaxation, color your leisure, turn your free time into relaxation, give a vacation from the daily for your mind, add zest, develop memory, develop logical thinking and concentration of attention. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko