The New Sudoku Players' Forum

[Pyrrhon]

Fill the numbers 1 through 9 into the cells so that each of rows, columns, boxes and marked diagonal lines contains every digit not more than once.

Puzzle 1:


Puzzle 2:

[udosuk]

Hopelessly stuck on your first puzzle...

Code: Select all

+-------------------------+-------------------------+--------------------------+
| 8       12      1459    | 12579   6       12579   | 24579   2579    3        |
| 1259    3       1459    | 12589   2578    5789    | 24579   6       5789     |
| 259     6       7       | 24589   3       24589   | 1       2589    589      |
+-------------------------+-------------------------+--------------------------+
| 12579   12      1589    | 2345789 2578    2345789 | 3579    3579    6        |
| 4       57      3       | 579     1       6       | 8       579     2        |
| 2579    578     6       | 235789  2578    235789  | 3579    1       4        |
+-------------------------+-------------------------+--------------------------+
| 357     578     2       | 1358    4       1358    | 6       589     589      |
| 13      9       158     | 6       2578    3578    | 2357    4       578      |
| 6       4       58      | 23578   9       23578   | 2357    23578   1        |
+-------------------------+-------------------------+--------------------------+

Any pointers please?

[Pyrrhon]

There is a Turbot fish with candidate 1 (strong links in B7 and B8, weak link in diagonal C2C9-C9C2) => R2C1 <> 1. Neither a triangualar connection nor a double crossover but I think, really another diagonal turbot fish step.

Pyrrhon

PS: For puzzlers which are not so familiar with the sudoku-x lingo, a double crossover is a turbot fish with two (not neighbored) strong links in diagonals, a triangular connection is a turbot fish with one strong link in a diagonal.

[udosuk]

Thanks for the tips! Solved #1, but stuck on #2 too...

[Jean-Christophe]

My turn to help you ... but not very much :

2 of C8 locked in R17C8 -> not in R7C2, R1C2
-> R4C2 = 2 (hidden single in C2)

And also
6 of C6 locked in R79C6 -> not in R9C8
2 of R8 locked in R8C14 -> not in R7C3

[udosuk]

Thanks JC! Your help is greatly appreciated...

I'm just going half-heartedly on sudoku/killers right now (hooked on h3lix's River game)...

[udosuk]

With JC's help the 2nd puzzle was solved too (excess use of turbot fish/crossover again)... Here are the solutions if anyone wants (drag and copy & paste to notepad):

819567423
234189567
567234189
128473956
453916872
976852314
782341695
391625748
645798231

586412793
317569248
249378516
125643987
678195432
493827165
951786324
764231859
832954671

[Pyrrhon]

Here my walk throughh puzzle 2. I skip naked singles.

Hidden Single 9 in B5, 6 in C3
Box-Line interaction B2 R1 => R1C1 <> 4
Box-Line interaction B4 C1 => R7C1 R9C1 <> 1
Box-Line interaction B6 C9 => R1C9 R3C9 <> 5
Turbot Fish with strong links B4 R8 => R2C4 <> 2
X-Wing with strong links in B9 R2 and weak links in diagonal R1C2-R8C9 C7 => R1C2 R1C7 <> 2
Box-Diagonal interaction B3 and diagonal R1C8-R8C1 => R3C6 R7C2 R8C1 <> 2
Hidden Single 2 in R8 C2 C6
Hidden Single 4 in B2, 5 in C4, 3 in B2, 7 in B2, 2 in R3, 8 in C5,
2 in B3 C8 R9
Naked Pair 8 9 in B2 => R7C6 R8C6 R9C6 R3C7 <> 89
Naked Pair 7 9 in B8 => R9C2 <> 9
Box-Line interaction B1 and C1 => R6C1 R7C1 R9C1 <> 3
Line-Box interaction C3 B4 => R4C1 R6C1 <> 5
Hidden Pair with 3 and 5 in diagonal R1C8-R8C1 (no candidate 6 in this diagonal) => R6C3 R7C2 ={35}=> R6C2 R7C3 <> 3
Hidden Single 3 in B4, 5 in R6 C3
Hidden Single 5 in diagonal R1C8-R8C1 (no candidate 6)
Hidden Single 4 in B6, 3 in B7, 8 in R5, 5 in B1 R3, 3 in C1, 7 in B1
Hidden Pair 1 6 in B3 => R3C8 R3C9 = {16}
Turbot Fish with strong links B3 B7 => R7C9 <> 1
Turbot Fish with strong links in C8 B7 => R7C7 <> 1
Hidden Single 1 in R7
Turbot Fish with strong links R8 C8 => R3C9 <> 1
Hidden Single 1 in B3
Naked Triple 789 in diagonal R2C9-R9C2 => R8C3 = 4
Hidden Single ...

586412793
317569248
249378516
125643987
678195432
493827165
951786324
764231859
832954671

[rechuk]

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