Eisbär (Arvid) and I have created a fresh sudoku advent calendar in which we combine a well known variant with a relatively unknown variant every day. Combining variants leads to interesting and surprising new solving techniques.
Logically solvable
All puzzles can be solved completely logically although the logic is sometimes well hidden and is inherent to the combination of restrictions that the different types offer. For that reason we have written some solving hints for most of the puzzles, published in a very tiny font. If you want to read the hints, simply copy these in a text editor and enlarge the font size.
Arrows
Place the digits from 1 to 9 in every row, column and 3x3-block. The digit in the point of the arrow is the sum of the other digits on the same arrow.
Edge Difference
Digits outside the grid indicate the difference between the first and the last digit in the corresponding row or column.
R2C1 = 1; R2C9 = 9; R1C7 = 1; R9C7 = 9; R6C8 = 9
R1C2 = 8/9; R1C1 = 7/8
R8C9 = 1/2; R8C1 = 8/9
8 in C9 in R7C9; R7C1 = 7/9
R1C1 + R78C1 = triplet {789}; R6C3 = 8; 9 in R5 in R5C3
R19C3 = pair {27}; R1C3 not 7 since it blocks possibilities for R19C2; R1C3 = 2
R9C3 = 7; R7C1 = 9; R8C1 = 8
Solution code: Column 4, followed by column 6.
on 29. March 2022, 12:32 by Nick Smirnov
F-puzzles:
https://f-puzzles.com/?id=yc72wxts
CTC App:
https://tinyurl.com/2p85e42f
on 7. December 2014, 16:25 by AnnaTh
Eisbär und Richard, thank you for this beautiful, intelligent calendar and all the work you put in. I enjoy it very much (and learn a lot).