Whirlpool
(Published on 20. September 2021, 13:04 by Xailran)
A river is a snake path of orthogonally connected cells starting next to a cage; the digit in that cage sets the length of the river. The number in the top-left corner of a cage sets the sum of the digits along the river. Rivers must decline in digit value from one direction to the other, starting from the cage. Rivers must not include cages. Rivers may touch themselves orthogonally, and rivers may overlap.
Summary: Rivers act as 'reverse thermometer arrows', with the controlling cage setting the length and total. Including the controlling cage, cages must not be in any river.
Rules Example
I hope you enjoy the puzzle and I am eager to hear how you go!
Solution code: Column 3
Comments
on 25. December 2021, 19:36 by Vebby
Superb! What a break-in! Best of the series in my opinion. I was thankfully able to find an entirely logical path without bifurcation. Great setting Xailran! :)
on 21. November 2021, 19:41 by jez9999
This required rather heavy bifurcation on the high value rivers; not really one of the better river puzzles in my opinion.
on 21. October 2021, 15:08 by Manycoloredcoat
Saw your initial puzzle with this ruleset on CTC and immediately liked it. This one was even better. Nice break-in, not to difficult to spot and great use of the longer rivers later on. I'm curious, which one of the river puzzles would you call your best?
It's also nice, that you included a CTC link, as it is by far the best app on mobile.
Response from Xailran: Thanks ManycoloredCoat! Interesting question. I really love River Sudoku, as it achieves exactly what it is meant to do as an intro to the ruleset. I really love Whirlpool for the break-in. Up The Swamp is also interesting, and perhaps more approachable than this one if you miss the break-in. Turbulence is somewhere between the two, but I particularly love the way the logic unravels (I'd rank it just below Up The Swamp).
