The New Sudoku Players' Forum

[Maria]

Can someone tell me what next step is, the technique to be used, and explanation - trying to improve

Code: Select all

xx7/6xx/8xx
2xx/x1x/63x
6xx/x4x/2x5
-----------------
x2x/9xx/16x
x1x/3xx/x2x
x86/xxx/xxx
-----------------
x42/59x/786
87x/2xx/95x
569/x78/3x2

Thanks

[JasonLion]

Without pencil marks I can't tell exactly how far you have gotten. From the puzzle as presented, you will need several locked candidates, a few naked pairs, and a sashimi X-wing, also called a skyscraper, to reduce it to singles.

[eleven]

Code: Select all

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

Look at the 1 in columns 1, 3 and 9. You only have 2 possibilities each (cells marked *).
They are forming 2 skyscrapers in colums 19 (2 * being in row 1, one of r7c1 and r9c8 must be 1) and 39 (row 8, one of r3c3 or r1c9 must be 1), both solve the puzzle.

See here for skyscrapers.

[Maria]

Without pencil marks I can't tell exactly how far you have gotten. From the puzzle as presented, you will need several locked candidates, a few naked pairs, and a sashimi X-wing, also called a skyscraper, to reduce it to singles.

I will check on eleven's - thank you so much.

[Maria]

Code: Select all

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

Look at the 1 in columns 1, 3 and 9. You only have 2 possibilities each (cells marked *).
They are forming 2 skyscrapers in colums 19 (2 * being in row 1, one of r7c1 and r9c8 must be 1) and 39 (row 8, one of r3c3 or r1c9 must be 1), both solve the puzzle.

See here for skyscrapers.

following yr advice and the link...... with patience I may succeeed - keep you posted - thanks for yr kind help

[ronk]

Can someone tell me what next step is, the technique to be used, and explanation

Without pencil marks I can't tell exactly how far you have gotten.

Maria, are you even using pencilmarks? If not, it would be helpful to say so at the outset, otherwise most people will assume you are.

Look at the 1 in columns 1, 3 and 9. You only have 2 possibilities each (cells marked *).
They are forming 2 skyscrapers in colums 19 (2 * being in row 1, one of r7c1 and r9c8 must be 1) and 39 (row 8, one of r3c3 or r1c9 must be 1), both solve the puzzle.

eleven, very nice pencilmark-less solution.

[Maria]

Can someone tell me what next step is, the technique to be used, and explanation

Without pencil marks I can't tell exactly how far you have gotten.

Maria, are you even using pencilmarks? If not, it would be helpful to say so at the outset, otherwise most people will assume you are.

Look at the 1 in columns 1, 3 and 9. You only have 2 possibilities each (cells marked *).
They are forming 2 skyscrapers in colums 19 (2 * being in row 1, one of r7c1 and r9c8 must be 1) and 39 (row 8, one of r3c3 or r1c9 must be 1), both solve the puzzle.

eleven, very nice pencilmark-less solution.

I am using nice pencilmarks... next time I will show.

[Maria]

Code: Select all

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

Look at the 1 in columns 1, 3 and 9. You only have 2 possibilities each (cells marked *).
They are forming 2 skyscrapers in colums 19 (2 * being in row 1, one of r7c1 and r9c8 must be 1) and 39 (row 8, one of r3c3 or r1c9 must be 1), both solve the puzzle.

See here for skyscrapers.

following yr advice and the link...... with patience I may succeeed - keep you posted - thanks for yr kind help

with this link everything is clear......