| Sudoku, or number placement, puzzles are | | | | cube has a number one as one of the given |
| sweeping the country. Even though the game | | | | numbers. That means that the number one you |
| involves numbers, it is not mathematical. And | | | | need to place must be located in the left or |
| people who feel they don't have a good | | | | right cube. Instead of 9 potential |
| vocabulary will choose them in preference to | | | | placements, you now have only 6.After you |
| crossword puzzles. Soduku is nothing more | | | | have determined all the missing numbers, you |
| than logic.Howard Gams is given credit for | | | | will find that you have many with two or |
| inventing the puzzle in 1979. His puzzles | | | | three possibilities. Hopefully you will be |
| never caught on in this country but became an | | | | able to write these possibilities in the |
| instant success in Japan. Now it is carried | | | | squares. The best you can hope for is to have |
| by more newspapers than crossword | | | | two contiguous squares with only two |
| puzzles.Soduku is a nine-by-nine cubical | | | | possibilities. In the top rank, squares one |
| grid. When properly completed, each of the | | | | and two are either a six or an eight, but you |
| rows and files will contain all the numbers | | | | can't tell which. You still have learned a |
| between 1 and 9 as will each of the 3 X 3 | | | | great deal of information because it means |
| cubes comprising the whole. The puzzle will | | | | that those two numbers can't appear in any of |
| appear as a completed grid with certain | | | | the other empty squares across that rank. As |
| numbers missing. When read across and down, | | | | I suggested before, every time you find a |
| each of the three contiguous inner cubes will | | | | "hard number," one that cannot be placed |
| have a different digit in a different | | | | anywhere else, fill it in with pen.Another |
| position. For our purposes we can designate | | | | way to come up with information is to use the |
| these rows as ranks and files. Ranks run | | | | "what if" method of placing numbers. Let's |
| horizontally across the puzzle and files, | | | | say that you have a six in the second rank of |
| vertically. If, for example, the number one | | | | the small cube in the upper left corner. Even |
| appears in rank 1 in cube one and rank 3 in | | | | if you have no other information where the |
| cube 2, the third one must necessarily appear | | | | other two 6s are located, you you know that |
| in the second rank in cube 3. This would seem | | | | the other 6s must be in first and third |
| to imply that it could appear in any of three | | | | ranks. By placing it in the first rank, you |
| positions in the second rank, but most often, | | | | will then have to locate the last placement |
| there will already be a number in one | | | | in the third rank of the remaining cube. By |
| position, leaving a choice of two | | | | testing the placements you will often run |
| possibilities. Let's assume you have a choice | | | | into a contradiction in one of the ranks or |
| of two positions.The next step is to check | | | | files. If you don't shrug your shoulders and |
| the files. If by some chance a one appears in | | | | try placing another number and see what |
| one of the files of your choices, you now | | | | happens.Kerep at it. Sooner or later you will |
| know the numeral must be placed in the other. | | | | have filled in most of the numbers. On more |
| This simple cross check should be your first | | | | than one occasion I have run into a |
| step in solving the puzzle. Anytime you find | | | | contradicition on the very last number. |
| a HARD number, one you have logically | | | | There's nothing to do about it but back up |
| determined cannot be another, I recommend you | | | | and start again. Patience is the greatest |
| write it in with a Pen. This will save | | | | skill required to solve thse puzzles.Sooner |
| unnecessary erasures when you make an | | | | or later, you, your pencil the paper or the |
| inevitable mistake.Your second step should be | | | | puzzle will call it quits. Let's hope it's |
| to scan each of the smaller cubes for their | | | | the puzzle.John Anderson is addicted to |
| missing numbers. Usually you will be able to | | | | puzzles in any of their forms. They play a |
| place one or two numbers by the rank-file | | | | crucial role in his novel, The Cellini |
| cross-checking. After you have done that, | | | | Masterpiece, written under the pen name of |
| read across each of the ranks and files to | | | | Raymond John. If you have a question or |
| determine the missing numbers. Let's say that | | | | comment for John, please log on to You also |
| you are missing a number one in the top rank | | | | may read the first chapter of The Cellini |
| and you have missing numbers in all of the | | | | Masterpiece at the site. |
| smaller cubes. Let's say that the middle | | | | |