You are given a wooden board and nine stones. Can you arrange all stones in the board such that in every row and in every column each color occurs only once?
If you fail to find a solution on your own, the five-colors application can do all the hard work for you. Spoiler alert: Reading the section below reveals the solution.
$ solve-five-colors...
Solution:
(1,1, vertical) blue green yellow
(1,2, vertical) yellow red
(1,3, horizontal) red black green
(2,3, horizontal) black blue yellow
(3,2, horizontal) blue green
(3,4, vertical) red yellow green
(3,5, vertical) black red blue
(4,1, horizontal) black green blue
(5,1, horizontal) red black yellow
Rotate and mirror this solution to produce variants of it.
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| B | Y | R | D | G |
| G | R | D | B | Y |
| Y | B | G | R | D |
| D | G | B | Y | R |
| R | D | Y | G | B |
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Board is valid and full.
Found 1 solution(s) in total.
Done after 12 ms.
A board size 5x5 is too easy for you? Here is a puzzle using a 6x6 board.
Still too easy? Use the generate-puzzle application to produce more.