Three Color Crusts
(Published on 14. September 2024, 12:17 by RockyRoer)
The Rules:
- [Killer Sudoku] Normal sudoku rules apply - fill every row and column with the digits from 1 to 7 once each. Digits in cages cannot repeat.
- [Crusts] Shade some cells using three different colors such that:
- In every cage there is one shaded cell, and in every row and column there are two shaded cells.
- Shaded cells cannot share an edge.
- Shaded cells of the same color cannot be in cages that share an edge.
- Shaded cells of the same color cannot be in the same row or column.
- Shaded cells of the same color must contain the same digit, shaded cells of different colors must contain different digits.
- [Prime Sandwich] Clues outside the grid represent the sum of the digits in the cells between the shaded cells. Each ? must be a *unique* 1- or 2-digit prime number - no repeats allowed.
The Puzzle:
Solution code: The unshaded cells in rows 3 and 7
Comments
on 29. September 2024, 04:50 by MattYDdraig
Naturally, I got too focused on the prime numbers to start off instead of the colouring. Unfolds beautifully once looked at the right way though.
on 18. September 2024, 05:11 by psams
This puzzle was fun and interesting all the way through - the coloring, deducing the primes and values for the shaded cells, and the normal sudoku. Very nice puzzle.
on 15. September 2024, 13:13 by RockyRoer
added sandwich tag
on 14. September 2024, 20:06 by marcmees
amazing puzzle. thanks
PS. 4th ° provided no extra needed info. :-)
Reply: Technically you're correct, but since the numbers don't exactly come into play right away, I thought it was helpful information to state at the beginning. And, to be completely transparent - the puzzle initially began as just a coloring exercise - then morphed into a different puzzle with modifiers, and finally into this one, so it's a bit of a legacy rule.
