How to Play Kakuro

Kakuro is a Japanese game that is similar to Sudoku. The game is also known by the name Cross Sums. Many newspapers print a Kakuro game in their daily newspaper, but it is only now starting to gain popularity in the United States. Here are the rules for playing Kakuro, and a list of tips that will help you get started.

Kakuro can seem confusing at first. There are some squares that have have one number, some that have one number over another, and some that have no number at all. If you think of it as a crossword puzzle, you will understand the way it works. The main similarity to Sudoku is that it only uses the numbers 1 through 9. Also, you may not use the same number in the same string. For example, if you have a string of two boxes and the clue is 6, you may not have two 3s.

Say you have the number 3 along the top row, and it is the only number in its box. You should also notice that there will be a string of two blank boxes directly beneath it. The reason is simple. The number 3 is your clue, and the boxes underneath it will add up to 3. If the number was 5 instead, the numbers would have to add up to 5, and so on. Because the only numbers between 1 and 9 that add up to 3 are 1 and 2, you know that one of the boxes will be a 1 and the other will be a 2. You must use the hints in the other boxes to give you a clue as to which one is which.

If you have two numbers in a Kakuro clue box, the one in the upper right corner is you clue for the boxes to the side of it. The number in the bottom left corner is your clue for the numbers below it.

The big trouble for a beginning player is when you have a very large number for your clue, or when the number has many different combinations. For example, say you have the number 41 and a string of 7 squares. That means you must find the correct position for 7 numbers which add up to the number 41. Obviously, this is difficult. Likewise, if you have the number 15 and a string of three boxes, there are quite a few combinations, and you must find not only the correct position, but even which numbers to use.

The greatest benefit to a Kakuro player is having a table that tells you the possible combinations that can be made. Often the Kakuro tables are listed in a format which specifies one number over another. For example, if you have the number 3 as a clue, and there are 2 squares, you are said to have "3 over 2". You look this up on the tables, and it tells you that the possibilities for those two squares are 1 and 2. This comes in very handy when you are dealing with large numbers. In the example given earlier where you have 41 over 7, a Kakuro table can quickly tell you that the possible numbers which can appear in those boxes are "2, 4, 5, 6, 7, 8, 9". In other words, the Kakuro table can tell you very quickly that you can rule out 1 and 3.

Remember that each string of numbers is both separate and joined to the other numbers. If you use a two in one string, you cannot use that in any other box, horizontally or vertically, as long as it is in the same string. However, with Kakuro, unlike Sudoku, if there is another clue in between, the number may be used again. This is the most helpful trick you have available. Say you have a horizontal area that only allows a 1 or a 2. If you can exclude a 1 from the first box, it must be a 2. That automatically makes the other box a 1. Then, if you have a long string of numbers below the 1, you can remove 1 as an option from all of these boxes. Likewise, if you have a clue that has many different options, but only one of them has a 1, you know exactly which numbers will appear, and can narrow it down from there. In other words, play a small area, but use the larger area to solve it.

The best tip for solving a Kakuro puzzle is to write down every number that can possibly be in a square first. Do this for every square. If there is only one number for that square, it must be that number. Then you can remove that number from the strings that connect to it, and work your way through the puzzle.

Finally, there are several Kakuro computer programs that allow you to use a "scratchpad" type feature. This helps you quickly add or eliminate them from your number options. Some also offer the tables built into the Kakuro program so that it tells you what numbers it could be when you move your mouse over the clue.These programs are great for beginners who may feel intimidated by having to constantly refer to a Kakuro chart.