The New Sudoku Players' Forum

[urhegyi]

I just created this windoku which solves with 2 xy-wings and 2 w-wings. Checked it by solving on paper.
There seems to be no solver I know that checks for w-wings.
But if anyone can confirm my solvepath?

Code: Select all

..5...8....82.61..2.......7...5.2.......8.......1.3...9.......3..28.97....1...6..


[m_b_metcalf]

But if anyone can confirm my solvepath?

Sorry, no, I don't have w-wings either. Nice puzzle though. Here's a (non-symmetric) harder, minimal version:

Code: Select all

...........8..61..2.......7...5.2.......8.......1.....9.......3..28.97....1...6..

Regards,

Mike

[1to9only]

I have some old development code (from many months ago) that solves the OP puzzle (SE Rating ED=4.1/1.2/1.2):

Solution Path: Show

Code: Select all

1: 1.2, Hidden Single: R3C6: 8 in block 2
2: 1.2, Hidden Single: R1C9: 6 in block 3
3: 1.2, Hidden Single: R1C8: 2 in block 3
4: 1.2, Hidden Single: R5C2: 2 in block 4
5: 1.2, Hidden Single: R6C8: 6 in block 6
6: 1.2, Hidden Single: R9C2: 8 in block 7
7: 1.2, Hidden Single: R7C8: 8 in block 9
8: 1.5, Hidden Single: R2C2: 7 in row 2
9: 1.5, Hidden Single: R4C8: 7 in row 4
10: 1.5, Hidden Single: R8C2: 3 in row 8
11: 2.6, Pointing: Cells R2C5,R3C5: 5 in block and column: -5r9c5, -5r8c5, -5r7c5
12: 2.6, Pointing: Cells R8C8,R8C9: 1 in block and row: -1r8c5
13: 2.8, Claiming: Cells R6C2,R6C3: 9 in row and block: -9r4c2, -9r5c3, -9r4c3
14: 2.6, Pointing: Cells R3C2,R3C3: 6 in block and windoku: -6r4c2, -6r4c3
15: 2.6, Pointing: Cells R2C5,R3C5: 5 in block and windoku: -5r2c9
16: 2.6, Pointing: Cells R2C8,R3C7,R3C8: 3 in block and windoku: -3r4c7
17: 2.6, Pointing: Cells R5C7,R5C8: 3 in block and row: -3r5c3, -3r5c1
18: 2.8, Claiming: Cells R3C3,R4C3: 3 in column and windoku: -3r3c4
19: 2.8, Claiming: Cells R8C1,R8C5: 6 in row and windoku: -6r7c5
20: 2.8, Claiming: Cells R3C2,R3C3,R3C4: 9 in windoku and row: -9r3c5, -9r3c7, -9r3c8
21: 2.6, Pointing: Cells R2C8,R2C9: 9 in block and row: -9r2c5
22: 2.8, Claiming: Cells R4C7,R5C7: 9 in column and block: -9r5c9, -9r5c8, -9r4c9
23: 3.0, Naked Pair: Cells R5C6,R6C5: 4,7 in block: -47r5c4, -4r4c5
24: 4.1, W-Wing: Cells R1C2,R1C5,R4C5,R2C9: 4 and 9: -4r2c1
25: 2.3, Naked Single: R2C1: 3
26: 1.2, Hidden Single: R4C3: 3 in block 4
27: 4.0, Hidden Triplet: Cells R1C5,R9C5,R9C9: 2,3,9 in windoku: -47r9c5, -45r9c9, -147r1c5
28: 2.8, Claiming: Cells R6C5,R7C5: 7 in column and windoku: -7r6c1
29: 4.1, W-Wing: Cells R2C9,R9C9,R1C5,R3C4: 4 and 9: -4r3c5, -4r3c7, -4r3c8, -4r2c5
30: 2.0, Direct Hidden Pair: Cells R2C8,R2C9: 4,9 in row: r2c5=5
31: 2.3, Naked Single: R3C5: 1
32: 1.2, Hidden Single: R1C1: 1 in block 1
33: 1.2, Hidden Single: R4C2: 1 in block 4
34: 1.2, Hidden Single: R5C8: 1 in block 6
35: 1.2, Hidden Single: R5C7: 3 in block 6
36: 1.2, Hidden Single: R3C8: 3 in block 3
37: 1.2, Hidden Single: R3C7: 5 in block 3
38: 1.2, Hidden Single: R4C7: 9 in block 6
39: 1.2, Hidden Single: R2C9: 9 in block 3
40: 1.0, Hidden Single: R2C8: 4 in block 3
41: 1.2, Hidden Single: R5C4: 9 in block 5
42: 1.2, Hidden Single: R1C5: 9 in block 2
43: 1.2, Hidden Single: R1C4: 3 in block 2
44: 1.2, Hidden Single: R1C6: 7 in block 2
45: 1.0, Hidden Single: R3C4: 4 in block 2
46: 1.0, Hidden Single: R1C2: 4 in row 1
47: 1.2, Hidden Single: R4C5: 6 in block 5
48: 1.2, Hidden Single: R5C3: 6 in block 4
49: 1.2, Hidden Single: R3C2: 6 in block 1
50: 1.0, Hidden Single: R3C3: 9 in block 1
51: 1.2, Hidden Single: R6C2: 9 in block 4
52: 1.0, Hidden Single: R7C2: 5 in column 2
53: 1.2, Hidden Single: R6C5: 7 in block 5
54: 1.0, Hidden Single: R5C6: 4 in block 5
55: 1.2, Hidden Single: R5C1: 7 in block 4
56: 1.0, Hidden Single: R5C9: 5 in row 5
57: 1.2, Hidden Single: R6C1: 5 in block 4
58: 1.2, Hidden Single: R4C1: 8 in block 4
59: 1.0, Hidden Single: R6C3: 4 in block 4
60: 1.0, Hidden Single: R7C3: 7 in column 3
61: 1.0, Hidden Single: R4C9: 4 in row 4
62: 1.2, Hidden Single: R6C9: 8 in block 6
63: 1.0, Hidden Single: R6C7: 2 in block 6
64: 1.0, Hidden Single: R7C7: 4 in column 7
65: 1.2, Hidden Single: R8C1: 6 in block 7
66: 1.0, Hidden Single: R9C1: 4 in block 7
67: 1.2, Hidden Single: R7C6: 1 in block 8
68: 1.0, Hidden Single: R9C6: 5 in column 6
69: 1.2, Hidden Single: R9C5: 3 in block 8
70: 1.2, Hidden Single: R7C5: 2 in block 8
71: 1.0, Hidden Single: R8C5: 4 in column 5
72: 1.0, Hidden Single: R7C4: 6 in row 7
73: 1.0, Hidden Single: R9C4: 7 in block 8
74: 1.2, Hidden Single: R8C9: 1 in block 9
75: 1.0, Hidden Single: R9C9: 2 in column 9
76: 1.0, Hidden Single: R8C8: 5 in row 8
77: 1.0, Hidden Single: R9C8: 9 in block 9


Edit: SudokuMonter's SukakuExplainer will also solve this, but the solution path is different.

[urhegyi]

Thank you 1to9only to verify my puzzle.
What I have remarked when trying to solve many puzzles is that w-wings are easy to spot in pencilmark grids and often reduce the difficulty from 7.1 (forcing chain) to 4.1 which is human solvable.
They are the first thing I check before resorting to more complex AIC's.