## Stuck with an hard puzzle on my iPhone (Amazing Sudoku)

Post the puzzle or solving technique that's causing you trouble and someone will help

### Stuck with an hard puzzle on my iPhone (Amazing Sudoku)

Can someone guide me on what my next step should be? Preferably by telling me to look at X row/col by using a certain techniques. I know most of the techniques from Basic Fish on up on this and I'd like to learn how to use more.
Code: Select all
`7 . . | 4 . . | . . .. 2 . | . . . | . . 3. . . | . 5 . | . . .------+-------+------. . . | . 8 . | . 9 4. . . | 7 4 5 | 6 . .8 4 . | 1 . . | . . .------+-------+------. . . | . . 4 | . . .4 . 9 | . . 2 | . 3 .1 3 6 | 9 7 8 | 5 4 2`

Normally, the hard puzzles in the app aren't too hard for me (takes me 20-30 mins ) but I don't know where to proceed on this.
cLin

Posts: 2
Joined: 17 November 2008

might be because the puzzle in the state that you posted has multiple solutions. are you sure you posted the puzzle with all givens correctly?
storm_norm

Posts: 85
Joined: 27 February 2008

to be honest, no. I saved a screenshot of it with some of my answers inserted already. Could be one of my inserts could of been false. Darn.
cLin

Posts: 2
Joined: 17 November 2008

cLin wrote:to be honest, no. I saved a screenshot of it with some of my answers inserted already. Could be one of my inserts could've been false. Darn.

Possibly, but by adding a wrong value to a valid puzzle you cannot increase the number of solutions from one to many, but only reduce the number from one to zero. You can go from one to many by leaving out a clue.

Regards,

Mike Metcalf

m_b_metcalf
2017 Supporter

Posts: 8983
Joined: 15 May 2006
Location: Berlin

Code: Select all
` +-------+-------+-------+ | 7 . . | 4 . . | . . . | | . 2 . | . . . | . . 3 | | . . . | . 5 . | . . . | +-------+-------+-------+ | . . 7 | . 8 . | . 9 4 | | . . . | 7 4 5 | 6 . . | | 8 4 . | 1 . . | . . . | +-------+-------+-------+ | . . . | . . 4 | . . . | | 4 . 9 | . . 2 | . 3 . | | 1 3 6 | 9 7 8 | 5 4 2 | +-------+-------+-------+`
There is a hidden pair in row 6.
eleven

Posts: 1800
Joined: 10 February 2008

Code: Select all
` +-------+-------+-------+ | 7 . . | 4 . . | . . . | | . 2 . | . . . | . . 3 | | . . . | . 5 . | . . . | +-------+-------+-------+ | . . 7 | . 8 . | . 9 4 | | . . . | 7 4 5 | 6 . . | | 8 4 . | 1 . . | . . . | +-------+-------+-------+ | . . . | . . 4 | . . . | | 4 . 9 | . . 2 | . 3 . | | 1 3 6 | 9 7 8 | 5 4 2 | +-------+-------+-------+`
There is a hidden pair in row 6.

Very likely. The posted version had 22 solutions, with these 46 clues in common:
Code: Select all
`  7 . 3 4 2 . . . . . 2 . 8 . . 4 . 3 . . 4 3 5 . 2 . . . . . 2 8 3 . 9 4 3 9 . 7 4 5 6 . . 8 4 . 1 . . 3 . . 2 . 8 . 3 4 . . . 4 . 9 . 1 2 8 3 . 1 3 6 9 7 8 5 4 2`

It has to be one of those missing, which yours is.

Regards,

Mike Metcalf

m_b_metcalf
2017 Supporter

Posts: 8983
Joined: 15 May 2006
Location: Berlin

m_b_metcalf wrote:It has to be one of those missing, which yours is.

.. and its the only one i found, which made it unique without having a single as the first move.
eleven

Posts: 1800
Joined: 10 February 2008