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This is a small Kakuro (Cross sums) puzzle which show how to use the technics described here. This is just one order in which you can solve the puzzle.
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This is the empty puzzle. |
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Rows and columns with only one possible combination of numbers. |
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The possible numbers for the sum 34 are 4, 6, 7, 8, and 9. For 7 they are 1, 2, and 4. The only one in common is 4. |
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The largest single number that can be found in a cell for the row whose sum is 9 is 6. That is because the other two cells require at least a 1 and a 2. Column 34 still has numbers 6, 7, 8, and 9 to be filled in, hence only 6 will fit in the given cell. |
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Only numbers 1 and 2 fit the top row and 1 and 3 fit the top-right column, therefore we place number 1 on the top right. Numbers 2 and 3 follow logically. |
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The row, whose sum is four, is still missing numbers 1 and 2. We know the correct order from two things:
- a) Only 2 is large enough to sum up to 11.
- b) Number 2 is required for the bottom right cell. Otherwise a sum can't be created for 19.
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And so on... |