Out of Operation
(Eingestellt am 23. August 2026, 11:00 Uhr von sacker)
I tried making another difference/sum lines puzzle and it turned out ok, but then most of the lines got erased - oopsie! Oh, wait... cool! No yeah, this is good. I think it’s still ok to try out. Yeah, it definitely is! Enjoy!
Sudoku: Standard rules apply (place the digits 1 to 9 in every row, column, and 3x3 box; there are even some given digits here!)
Difference line (thicker, blue line): The two digits on a line’s endpoints have an absolute difference equal to the digit on the midpoint.
Sum lines (thinner, pink lines): The two digits on a line’s endpoints sum to the digit on the midpoint.
Unknown Operation lines (hollow lines): Each line operates as either a Difference line or a Sum line (left for you to deduce).
Solve this puzzle in SudokuPad.
(Below are some potentially patronizing hints for the solve path. I've gotten feedback from friends who are new to variant sudoku that it may help to have access to pointers like these, especially given the tough start that this puzzle has. So only use the hints if you need to, and go one by one to avoid spoilers.)
1a. Start with pencil-marking. From the given 9's, pencil-mark the possibilities along their hollow lines and adjoining sum lines (up to r2c6 and r8c4). Also pencil-mark r2c2 and r1c3, realizing the relationship these two cells have along the sum line. Now, let's assume that the given 5 is NOT the largest digit on its line. If so, math forces r8c6, the pencil-marking plus more math forces r8c2, and then see what happens in the upper-left.
1b. This same method works if you instead start with the given 6 and question whether it is NOT the largest digit on its line. Although this path is slightly more convoluted than 1a (you can still verify it yourself), 1a and 1b both prove the relative size of the given 5 and given 6 on their respective lines.
2. If you managed to get through that first step, you're probably set. But if resolving the two mountain peaks (r3c5 and r7c5) is tripping you up, figure out where 1 must go in row 1 and where 2 must go in row 9.
3. After solving the mountain/valley features in rows 1-3 and 7-9, try finding where a couple extra 9's could be placed, especially in box 9.
4. Now consider whether it’s possible for 3 to NOT appear on the given difference line, given the digits in box 9 and the other digits in column 8. With that in mind plus some sudoku, you'll see that there are only three possible digits that can fill the vertical line in column 2.
5. You've got it from here!
Sudoku: Standard rules apply (place the digits 1 to 9 in every row, column, and 3x3 box; there are even some given digits here!)
Difference line (thicker, blue line): The two digits on a line’s endpoints have an absolute difference equal to the digit on the midpoint.
Sum lines (thinner, pink lines): The two digits on a line’s endpoints sum to the digit on the midpoint.
Unknown Operation lines (hollow lines): Each line operates as either a Difference line or a Sum line (left for you to deduce).
Solve this puzzle in SudokuPad.
(Below are some potentially patronizing hints for the solve path. I've gotten feedback from friends who are new to variant sudoku that it may help to have access to pointers like these, especially given the tough start that this puzzle has. So only use the hints if you need to, and go one by one to avoid spoilers.)
1a. Start with pencil-marking. From the given 9's, pencil-mark the possibilities along their hollow lines and adjoining sum lines (up to r2c6 and r8c4). Also pencil-mark r2c2 and r1c3, realizing the relationship these two cells have along the sum line. Now, let's assume that the given 5 is NOT the largest digit on its line. If so, math forces r8c6, the pencil-marking plus more math forces r8c2, and then see what happens in the upper-left.
1b. This same method works if you instead start with the given 6 and question whether it is NOT the largest digit on its line. Although this path is slightly more convoluted than 1a (you can still verify it yourself), 1a and 1b both prove the relative size of the given 5 and given 6 on their respective lines.
2. If you managed to get through that first step, you're probably set. But if resolving the two mountain peaks (r3c5 and r7c5) is tripping you up, figure out where 1 must go in row 1 and where 2 must go in row 9.
3. After solving the mountain/valley features in rows 1-3 and 7-9, try finding where a couple extra 9's could be placed, especially in box 9.
4. Now consider whether it’s possible for 3 to NOT appear on the given difference line, given the digits in box 9 and the other digits in column 8. With that in mind plus some sudoku, you'll see that there are only three possible digits that can fill the vertical line in column 2.
5. You've got it from here!
Lösungscode: Row 6, left to right
Zuletzt geändert -
Gelöst von jalebc, zeniko, SKORP17, sanabas, m0rkoli, kangaroo
Kommentare
am 24. August 2026, 08:13 Uhr von zeniko
Nice setting, thanks for sharing.
For the visuals, have you tried using a consistent, finer line width, more popping colors and light grey for the ambiguous lines? That might make the puzzle look even more appealing.
