Everyone knows sudoku is enjoyable--but these addictive puzzles come in endless variations too! They range from simple to very difficult, and can take almost no time to finish...or require many hours. This entertaining collection showcases a wide range of possibilities, offering solvers who have become accustomed to the standard rules and grids an exciting new challenge. Select from Mega Sudokus that provide a real workout; Diagonals or Odd and Even versions with extra constraints; Sum Sudokus that merge with kakuro; and Multisudoku with overlapping puzzles. There's something for every level--12 x 12 puzzles, ones with irregularly shaped areas, even Mini Sudoku--and lots of fun for everyone.

You don't need to be a math expert to enjoy a sudoku--all you need is a logical mind, so sharpen your pencils and brace your brain for this collection of sudoku puzzles. There are more than 540 brand new puzzles of ranging difficulty-- a feast for sudoku addicts everywhere!

Packed with more than a hundred color illustrations and a wide variety of puzzles and brainteasers, Taking Sudoku Seriously uses this popular craze as the starting point for a fun-filled introduction to higher mathematics. How many Sudoku solution squares are there? What shapes other than three-by-three blocks can serve as acceptable Sudoku regions? What is the fewest number of starting clues a sound Sudoku puzzle can have? Does solving Sudoku require mathematics? Jason Rosenhouse and Laura Taalman show that answering these questions opens the door to a wealth of interesting mathematics. Indeed, they show that Sudoku puzzles and their variants are a gateway into mathematical thinking generally. Among many topics, the authors look at the notion of a Latin square--an object of long-standing interest to mathematicians--of which Sudoku squares are a special case; discuss how one finds interesting Sudoku puzzles; explore the connections between Sudoku, graph theory, and polynomials; and consider Sudoku extremes, including puzzles with the maximal number of vacant regions, with the minimal number of starting clues, and numerous others. The book concludes with a gallery of novel Sudoku variations--just pure solving fun! Most of the puzzles are original to this volume, and all solutions to the puzzles appear in the back of the book or in the text itself. A math book and a puzzle book, Taking Sudoku Seriously will change the way readers look at Sudoku and mathematics, serving both as an introduction to mathematics for puzzle fans and as an exploration of the intricacies of Sudoku for mathematics buffs.

Google Android dominates the mobile market, and by targeting Android, your apps can run on most of the phones and tablets in the world. This new fourth edition of the #1 book for learning Android covers all modern Android versions from Android 4.1 through Android 5.0. Freshly added material covers new Android features such as Fragments and Google Play Services. Android is a platform you can't afford not to learn, and this book gets you started. Android is a software toolkit for mobile phones and tablets, created by Google. It's inside more than a billion devices, making Android the number one platform for application developers. Your own app could be running on all those devices! Getting started developing with Android is easy. You don't even need access to an Android phone, just a computer where you can install the Android SDK and the emulator that comes with it. Within minutes, Hello, Android gets you creating your first working application: Android's version of "Hello, World." From there, you'll build up a more substantial example: an Ultimate Tic-Tac-Toe game. By gradually adding features to the game, you'll learn about many aspects of Android programming, such as creating animated user interfaces, playing music and sound effects, building location-based services (including GPS and cell-tower triangulation), and accessing web services. You'll also learn how to publish your applications to the Google Play Store. This fourth edition of the bestselling Android classic has been revised for Android 4.1-4.3 (Jelly Bean), 4.4 (KitKat), and Android 5.0 (Lollipop). Topics have been streamlined and simplified based on reader feedback, and every page and example has been reviewed and updated for compatibility with the latest versions of Android. If you'd rather be coding than reading about coding, this book is for you.

Heyawake (from Japanese, "divided rooms") is played on a rectangular grid. The grid is divided into rectangular "rooms". Some rooms may contain a single number. These rooms must have the designated number of cells painted black. Other rooms may have zero or more cells painted black. Black cells must not be orthogonally connected. All white cells must be interconnected. A line of connected white cells must not connect more than two rooms together.

Its time to break out of the box: the traditional 3x3 puzzle box, that is! This assortment of engaging and challenging variants takes sudoku up a notch. The creative twists include overlapping and unusually shaped grids, special rules that make solvers up their game, and even super-large sudoku for an extra-fun experience.

The ultimate Sudoku title: not just a puzzle book, but a comprehensive encyclopedia of the phenomenon to date, featuring every major variant ever created. Here you will find close to 150 different kinds of Sudoku in 495 puzzles, including Killer Sudoku, Skyscraper Sudoku and multi-grid Samurai Sudoku. No other collection of Sudoku comes close; this is without doubt the most definitive volume of Sudoku variants ever compiled. Another blockbuster from the puzzle master behind the bestselling Mammoth Book of Sudoku.