The Dutch puzzle association WCPN is proud and excited to announce a fun online sudoku contest in the last week of 2025!
The contest consists of eight tougher sudoku variants. At the time that fits you best between 24 and 31 december you can start the contest and you then have 2,5 hours time to submit as many answers as possible. The puzzles are in pdf-format, like the grand prix and (qualifiers for) national championships.
The puzzle below was not selected for the contest, but suits very well as appetizer. The day after tomorrow I will publish one more appetizer.
Sudoku - Weiqi
Solve online in Sudokupad. (No solution checking.)
An easier example of this type can be found here: SVS #405
The contest is open to everybody who loves sudokus. The only thing you have to do is register yourself (at no cost) here. You can find the instruction booklet (IB) with all the info here.
Enjoy!
Verwende die üblichen Sudoku-Regeln.
Für jeden schwarzen Kreis ist die Summe der Ziffern in den angrenzenden Kästchen größer als 19 (für 2 mal 2 Kästchen), 9 (für zwei Randkästchen) bzw. 4 (für ein Eckkästchen). Für jeden weißen Kreis ist die Summe der Ziffern kleiner als 19, 9 oder 4.
Alle möglichen Kreise sind gegeben.
Solve online in Sudokupad. (With solution checking.)
(If you want to participate in the contest, it is recommended to solve this puzzle on paper too. ;)
Lösungscode: Zeile 6
am 21. Dezember 2025, 10:00 Uhr von Piatato
Very nice!
am 21. Dezember 2025, 07:31 Uhr von Sandy329
This is the most challenging puzzle I have completed on my own so far
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Reply: Well done! It's not an easy one at all. ;)
am 21. Dezember 2025, 02:43 Uhr von walid_tun
I liked the logic. It's like multi-layered whispers.
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Reply: thanks! I think it is a variant that offers a lot of different solving and setting options. Although solving will be often a time consuming activity. :)
am 20. Dezember 2025, 21:06 Uhr von SennyK
This one was pretty challenging, I really liked the logic though! Thank you for setting :-)
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Reply: thanks for your kind words, and not only for this one!