Parity Snakes Sudoku 3b
(Published on 31. May 2020, 04:00 by Eggr)
If this puzzle looks familiar please read the bold rules carefully.
This is my 3rd puzzle of this variant (presumably the hardest). Try the first and second puzzles if you haven't already.
Rules:
Normal Sudoku rules apply.
The highlighted cells are the heads and tails of the 3 snakes found within the grid:
2 Odd Snakes (only contain odd digits) and 1 Even Snake (only contains even digits)
Snakes do not touch. (orthogonality or diagonally).
Clues outside the grid show the total number of snake cells in the corresponding row or column.
Puzzle:
Disambiguation:
The ends of the snakes are given, but which ones are connected, and their parity, must be determined.
Each 'snake' is a 1-cell wide path of orthogonality connected cells, starting at the 'head' and leading to the 'tail'.
Snakes never touch each other. (Including diagonally)
Snakes never touch themselves. (Including diagonally)
Snakes never 'double-back' to cover a 2x2 region.
Digits outside the snakes have no special restrictions
Hints:
Don't forget the snake parities (2 Odd Snakes, 1 Even Snake)
If you're struggling to get started, highlight the text below to reveal some strategy recommendations:
[Hints] 1. The Odd/Even restriction on each snake is very powerful. Remember that basic Sudoku rules require exactly 4 Even digits, and 5 Odd digits to be in each row, box, and column. Many potential snake paths can be eliminated based on those restrictions. Many other paths can be eliminated based on the outside clues.
2. Starting this puzzle: It's possible to resolve the parity of all 6 endpoints very early on by studying R9 [/Hint]
This puzzle has a second solution (with 1-Odd and 2-Even snakes) Use this link to enter the other solution if you haven't already.
Created by Greg Rodgers Powers
This is my 3rd puzzle of this variant (presumably the hardest). Try the first and second puzzles if you haven't already.
Rules:
Normal Sudoku rules apply.
The highlighted cells are the heads and tails of the 3 snakes found within the grid:
2 Odd Snakes (only contain odd digits) and 1 Even Snake (only contains even digits)
Snakes do not touch. (orthogonality or diagonally).
Clues outside the grid show the total number of snake cells in the corresponding row or column.
Puzzle:
Disambiguation:
The ends of the snakes are given, but which ones are connected, and their parity, must be determined.
Each 'snake' is a 1-cell wide path of orthogonality connected cells, starting at the 'head' and leading to the 'tail'.
Snakes never touch each other. (Including diagonally)
Snakes never touch themselves. (Including diagonally)
Snakes never 'double-back' to cover a 2x2 region.
Digits outside the snakes have no special restrictions
Hints:
Don't forget the snake parities (2 Odd Snakes, 1 Even Snake)
If you're struggling to get started, highlight the text below to reveal some strategy recommendations:
[Hints] 1. The Odd/Even restriction on each snake is very powerful. Remember that basic Sudoku rules require exactly 4 Even digits, and 5 Odd digits to be in each row, box, and column. Many potential snake paths can be eliminated based on those restrictions. Many other paths can be eliminated based on the outside clues.
2. Starting this puzzle: It's possible to resolve the parity of all 6 endpoints very early on by studying R9 [/Hint]
This puzzle has a second solution (with 1-Odd and 2-Even snakes) Use this link to enter the other solution if you haven't already.
Created by Greg Rodgers Powers
Solution code: (2-Odd and 1-Even Snake Solution) Row 6
Last changed on on 7. June 2020, 07:12
Solved by zhergan, cdwg2000, TwisterMonkey, Marijana, moss, Madmahogany, zorant, NikolaZ, Mody, geronimo92, sandmoppe, OJPS, Jesper, sf2l, Johan
Comments
on 15. June 2020, 17:03 by Mody
Großartig, zwei gleiche Gitter mit gleichen Vorgaben und beide Male mit schönem Lösungspfad, Hut ab vor dieser Konstruktion.
on 31. May 2020, 12:42 by cdwg2000
Nice one.
It seems that 2 even snakes + 1 odd snake is also the only solution.
on 31. May 2020, 09:08 by zhergan
Nice and surprising :))
