The New Sudoku Players' Forum

[enxio27]

Here is puzzle #28 from the now-defunct Sudoku Magazine's Sudoku Mix #1. As you can see from the second image, I've gotten stuck. Richard Broughton's SudokuSolver gives me errors when trying to get hints or solve (from either point), although it says its a valid puzzle. Am I doing something wrong or missing something, or is there something wrong with the puzzle itself? (I've addressed the SudokuSolver errors themselves elsewhere.) The puzzle code:

Code: Select all

SumoCueV1=0J0=7J0=0J0=0J1=0J1=0J1=0J1=1J2=0J2=4J0=0J0=9J3=0J1=0J1=0J1=1J1=0J2=8J2=0J0=1J0=0J3=2J3=0J1=6J4=0J2=4J2=0J2=0J0=0J0=5J3=1J3=0J4=4J4=6J5=0J5=0J2=0J6=0J3=0J3=0J4=1J4=0J4=0J5=0J5=0J2=0J6=0J3=8J3=3J4=0J4=1J5=4J5=0J7=0J7=0J6=8J6=0J6=5J4=0J8=9J5=0J5=6J7=0J7=7J6=0J6=2J8=0J8=0J8=0J8=3J5=0J7=1J7=0J6=2J6=0J8=0J8=0J8=0J8=0J7=3J7=0J7


[999_Springs]

strong link of 8 in c4 weakly linked to 58 cells in r3c5 and r9c7 oh look it's a w-wing thingy

10 cells later there's another w-wing thingy with the strong link of 2 in r4 and some 25 bivalues somewhere ughhh i've been hiking all day and i hate hiking and it's 1am and i'm tired zzz

jigsaws are cool

[enxio27]

w-wing thingy? Not sure I'm familiar with that.

[999_Springs]

sudopedia mirror article on w-wing

it's a bilocation with 2 bivalue cells sticking out of it. in your grid as shown, there are 2 bivalue cells 58 in r3c5 and r7c9. there's a strong link of 8 in c4, which is weakly linked to both bivalues. if the 8 in r1c4 is true, that forces 5 to be true in r3c5; and if the 8 in r9c4 is true, that forces 5 to be true in r9c7. either way, at least one of r3c5 and r9c7 must be a 5.

that means you can get rid of 5 in any cell that can see both things, so here r3c7 can't be a 5.

see if you can find the 2nd w-wing 10 cells later in this puzzle. i stuck the name "thingy" after it because this is a jigsaw and not a standard puzzle

to find these things by hand, i find it easier to spot the two bivalue cells first, like a naked pair "in the wrong place", then search for a bilocation

[enxio27]

Ahhh. . . Thanks for the explanation! I still haven't made it up to w-wings. I've gotten only as far as swordfish (and still haven't found one that actually eliminated any candidates).