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Triple shoot trick to solve diabolical puzzle

 
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mahadevan



Joined: 18 Nov 2009
Posts: 6
Location: india bangalore

PostPosted: Wed Nov 18, 2009 3:44 am    Post subject: Triple shoot trick to solve diabolical puzzle Reply with quote

Hi all,
I really need some inputs on this technique.

http://picasaweb.google.com/tajomaysudoku/Sudoku#5405276178561943026

Experience shows that in Diabolical puzzle triplets are difficult to spot. Hence the Arrow shoot / Triple shoot
trick has been devised and experimented.

Authenticity of this trick has to be explored through other puzzles.

After fixing the straight numbers in all nonets, some twins in the same nonets or triplets in two regions or cells triplet in two cells
were pencilled.

Though the author in the above book suggested to apply Adriane's trick i.e.
try with one approach and in case of failure, try the other route.

But a successful attempt was made to solve this puzzle with a new approach i.e. "Arrow shoot".

The purpose is to fix the 3 and 5 in Nonet 1 i.e. either 3 left or right.

Scrutinise the Nonet 7 wher 3s are in two rows i.e. R7 and R8. This nonet has 3s in a row (R8) and two 3s in R7
Irrespective of the row the 3s in this nonet have formed an arrow i.e. three 3s in a row and 3 in the middle of R7.
With the arrow like 3s if the journey starts to fix the 3 in Nonet, the journey ends in nonet 1 - R3 - C2.


Hence R3 C3 becomes 5.
(Of course 35 in Nonet 4 was written after resolving Nonet 1 and 7

After this the puzzle has an easy flow and can be completed in the normal way.

Anyone can suggest a still better method.

Definition of some terminologies
Nonet : a Region consisting of 9 cells

R = Row
C = Column

Regards,
Mahadevan
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Wed Nov 18, 2009 6:08 am    Post subject: Reply with quote

the puzzle has 195 solutions.
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Mogulmeister



Joined: 03 May 2007
Posts: 1151

PostPosted: Wed Nov 18, 2009 8:06 am    Post subject: Reply with quote

Mahadevan,

What I believe you have there is an early Michael Mepham when sudokus with multiple solutions were still being set as puzzles. The other giveaway is the use of Ariadne's thread as a technique - which is essentially a trial and error technique that he championed early in the evolution of this game (or sickness as Marty calls it).

The majority of puzzle setters these days set sudokus to have one solution and -although still contentious- many purists look for logical or a priori solve paths rather than guesswork to complete them.

Perhaps we could see the arrow shoot on some other diabolical or Extreme puzzles ?
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daj95376



Joined: 23 Aug 2008
Posts: 3854

PostPosted: Wed Nov 18, 2009 10:52 am    Post subject: Reply with quote

If you examine the PM grid next to the puzzle, you'll see that given r2c5=2 has been converted into solved cell r2c6=2. You need to find another source for puzzles.
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