(also known as " ", " ") is a new logic puzzle that you can solve by using only zeros and ones. The rectangular or square grid should fill the numbers in accordance with the following rules: - Each row and each column contain the same number of digits " " as digits " " (or one more for odd sized grids). - The same number can only be in no more than two cells in a row. - Each line must be unique, and each column must be unique. The puzzle book contain: - 200 Puzzles - Handy 6 x 9 inch Book Layout - 2 Puzzles per Page - Ideal for Experts In the book you will find a description and examples of solutions for all puzzles. The book is for those who like logic and math problems. Decide, developing and improving.