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How Futoshiki Puzzles Work

All you need to solve a futoshiki puzzle is your brain and a pencil. See a step-by-step guide to solving a futoshiki puzzle.

Who doesn't love a good challenge now and then? Based on the popularity of logic games like crossword puzzles and sudoku grids, it seems we really enjoy a good brainteaser. And today, a logic game that spawned in Japan is starting to spread across the globe -- the United Kingdom appears to have gone mental over it. There are two names we commonly use for the game: futoshiki or hutosiki.

The word Futoshiki means "unequal" in Japanese and that's the key to the game. At first glance, a futoshiki puzzle looks a lot like a sudoku grid. The game consists of rows and columns of boxes. The grid is a square. One of the most common layouts for a Futoshiki grid is a 5-by-5 grid, meaning each row and column consists of five smaller squares.

Your goal as a player is to fill in these squares with digits. The number of digits depends upon the size of the grid. If it's a five-by-five grid, you'll need to fill in the digits one through five in each row and column. That means the same digit can't appear twice in a single row or column.

To guide you in your digit-depositing quest, you'll see some symbols on the grid. These are inequality symbols -- also known as the less-than and greater-than symbols we use in math. These symbols restrict which digits can fit into a particular square. Depending on the puzzle, you may have a number or two provided for you to give you a bit of a start.

So how do you solve a Futoshiki puzzle?

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