The New Sudoku Players' Forum

[JeJ]

Hi

I have this puzzle that starts as:

Code: Select all

1 . 9|. . .|. . .
4 . .|1 . .|5 . .
. . .|6 . .|3 7 .
-----------------
5 2 .|. 4 .|8 . .
. . .|5 . 1|. . .
. . 7|. 8 .|. 5 2
-----------------
. 1 4|. . 8|. . .
. . 6|. . 7|. . 3
. . .|. . .|7 . 4


After working on it for a while I get to a point where there seem to be 3 BUG+1 situations at blocks 5, 6 and 9. Aren't these BUG's? Because if I fill the cell with the third digit (the one that is in the cell with 3 pencilmarks), I get to and error. So could someone please explain if I am missinterpreting this BUG thing? thanks. Here's the puzzle with the mentioned bugs:

Code: Select all

1    7    9   |8    35   35  |24   24   6
4    6    3   |1    7    2   |5    9    8
28   58   25  |6    9    4   |3    7    1
---------------------------------------------
5    2    1   |7    4    36  |8    36   9
369  349  8   |5    2    1   |46   346  7
369  349  7   |39   8    369 |1    5    2
---------------------------------------------
7    1    4   |239  36   8   |269  26   5
289  589  6   |4    15   7   |29   18   3
2389 3589 25  |239  1356 3569|7    18   4


[daj95376]

http://www.sudopedia.org/wiki/Bivalue_Universal_Grave

[JeJ]

http://www.sudopedia.org/wiki/Bivalue_Universal_Grave

Exactly from there I took the explanation about BUG+1. the example shows a situation just like mine (or at least that Is what I think). In the example, the cells have the numbers 5,9 ; 579 and 79 and in my example I have:

On Block 5: 3,6 ; 3,9 and 3,6,9

On block 6: 3,6 ; 4,6 and 3,4,6

And on block 9: 2,6,9 ; 2,6 and 2,9

Are these situations mere triplets and not real bug+1 situations?

[ronk]

The very first sentence of that sudopedia link is ...

"A Bivalue Universal Grave or BUG+0 is a state of the grid in which every unsolved cell has 2 candidates ..."

That's involves all 81 cells of the grid, not just the 9 cells of one 3x3 box at a time.

[edit: "BUG+0" was "BUG"]

[JeJ]

Then there is something that I don't understand. If A Bivalue Universal Grave or BUG is a state of the grid in which every unsolved cell has 2 candidates, how come the example shows 3 candidates at r1c5?

[ronk]

Then there is something that I don't understand. If A Bivalue Universal Grave or BUG is a state of the grid in which every unsolved cell has 2 candidates, how come the example shows 3 candidates at r1c5?

The example is of a BUG+1, meaning 1 cell has more than 2 candidates.

[andyistic]

[quote="JeJ"]Hi

I have this puzzle that starts as:

Code: Select all

1 . 9|. . .|. . .
4 . .|1 . .|5 . .
. . .|6 . .|3 7 .
-----------------
5 2 .|. 4 .|8 . .
. . .|5 . 1|. . .
. . 7|. 8 .|. 5 2
-----------------
. 1 4|. . 8|. . .
. . 6|. . 7|. . 3
. . .|. . .|7 . 4


Singles, Pairs, and Confined are sufficient methods for solving this particular puzzle.

Solution:

Code: Select all

179|853|426
463|172|598
285|694|371
-----------
521|746|839
398|521|647
647|389|152
-----------
714|238|965
956|417|283
832|965|714


[Pat]

Code: Select all


 1 . 9 | . . . | . . .
 4 . . | 1 . . | 5 . .
 . . . | 6 . . | 3 7 .
-------+-------+------
 5 2 . | . 4 . | 8 . .
 . . . | 5 . 1 | . . .
 . . 7 | . 8 . | . 5 2
-------+-------+------
 . 1 4 | . . 8 | . . .
 . . 6 | . . 7 | . . 3
 . . . | . . . | 7 . 4



Singles, Pairs, and Confined are sufficient methods for solving this particular puzzle.

yes, a nice puzzle --
after "hidden singles", combine 2 moves to solve the next cell --

·:·

• b5 6: in c6
• in b9, "hidden" duo {1,8}
combine --> r9 6

·:·