Negative Sudoku
(Published on 20. November 2020, 06:00 by ibogdank)
To solve this Sudoku, you must place digits from 1 to 9, but be aware that there exists also negative numbers!
So, like standard Sudoku, each of the rows, columns and 3x3 boxes contains exact one of the 1 - 9 values in their absolute value. But, in the whole grid, there are 9 negative numbers: -1, -2, … to -9, one of each. Every row, every column and every 3x3 box contains exactly one negative number. The negative numbers do not touch not even diagonally (anti-king constraint: each negative number does not have another one in its eight neighbors).
Every negative number belongs to a killer cage. There is no killer cage with more than one negative number. The clues inside the cages give the sum of the numbers included, considering the negative ones, also. For example, if a cage sum is 11, then the cage could have this content: 5, 8 and -2. In a cage, numbers cannot repeat if we consider their absolute value.
The little killer clue outside the grid give the sum of the indicated diagonal.
Note: The three given digits are not negative.
F-puzzles - it shows errors while solving, because it expects normal rules.
Solution code: The contents of row 2, followed by column 7. Do not include the minus sign. Write only the 18 digits.
Comments
on 20. November 2020, 21:48 by ibogdank
@SenatorGronk, thanks for the hints.
Your puzzle is interesting too.
In mine, I gave the indication about the cages because they spanned on 2 boxes, and I thought it might be helpful.
on 20. November 2020, 21:43 by ibogdank
F-Puzzle: Disabled conflicts and added rules.
on 20. November 2020, 17:22 by SenatorGronk
For future reference: You can change the settings in F-puzzles not to check conflicts. It also allows you to add instructions which will appear in the left panel.
I made a similar puzzle last month: https://logic-masters.de/Raetselportal/Raetsel/zeigen.php?id=0004E6
It has "poisoned" digits with the same layout constraints as your negative numbers (in my puzzle they have a value of 0, not negative). I found the "poisoned" label made it easier to explain their impact on the traditional rules (little killer in my case).
I haven't gotten too far in your puzzle yet, but I was able to conclude that no killer cage has more than one negative number without needing that explicitly stated.
