Thread - HITORI

@ 2011-05-07 11:18 PM (#4325 - in reply to #4324) (#4325) Top

sanket

Posts: 17

Country : India

sanket posted @ 2011-05-07 11:18 PM

hmm..
yeah i started in the same manner as you mentioned...
and what about the reversal rule?
thanks anyway :)

@ 2011-05-08 3:04 AM (#4326 - in reply to #4325) (#4326) Top

Valezius

Posts: 66

Country : Hungary

Valezius posted @ 2011-05-08 3:04 AM

sanket - 2011-05-07 11:18 PM

hmm..
yeah i started in the same manner as you mentioned...
and what about the reversal rule?
thanks anyway :)

The reversal rule is true because if you find a solution where an unique (yellow) number is black then you can change this black square to yellow. And you will have another correct solution. So there is a solution where every unique number is yellow. And if the puzzle is correct this is the unique solution.

@ 2012-05-09 6:15 PM (#7225 - in reply to #4321) (#7225) Top

csraveen

Posts: 4

Country : India

csraveen posted @ 2012-05-09 6:15 PM

If a number appears only once in a row/column is it necessary to circle it?????and if a number appears more than once in a row/column is it necessary to circle one of them??????

@ 2012-12-15 6:57 AM (#9129 - in reply to #4323) (#9129) Top

chaotic_iak

Posts: 241

Country : Indonesia

chaotic_iak posted @ 2012-12-15 6:57 AM

sanket - 2011-05-07 9:44 PM

Also the rules of hitori say that a number cannot appear more than once.
So can we use the reverse rule : Circling a particular number (or shading in yellow as in above case) if its another occurence in the same row/column has been shaded (in grey color as in above) because this ensures that the number will always occur once (and cannot appear 'zero' times) ?

Not necessarily. Try this:
1112
2341
1213
2421

Observe C3. Both of its 1s are shaded, leaving no 1 remaining.

To above: The first is yes if the solution is guaranteed to be unique (but no otherwise), the second is no.


	@ 2011-05-07 11:18 PM (#4325 - in reply to #4324) (#4325) Top
sanket Posts: 17 Country : India	sanket posted @ 2011-05-07 11:18 PM hmm.. yeah i started in the same manner as you mentioned... and what about the reversal rule? thanks anyway :)
	@ 2011-05-08 3:04 AM (#4326 - in reply to #4325) (#4326) Top
Valezius Posts: 66 Country : Hungary	Valezius posted @ 2011-05-08 3:04 AM sanket - 2011-05-07 11:18 PM hmm.. yeah i started in the same manner as you mentioned... and what about the reversal rule? thanks anyway :) The reversal rule is true because if you find a solution where an unique (yellow) number is black then you can change this black square to yellow. And you will have another correct solution. So there is a solution where every unique number is yellow. And if the puzzle is correct this is the unique solution.
	@ 2012-05-09 6:15 PM (#7225 - in reply to #4321) (#7225) Top
csraveen Posts: 4 Country : India	csraveen posted @ 2012-05-09 6:15 PM If a number appears only once in a row/column is it necessary to circle it?????and if a number appears more than once in a row/column is it necessary to circle one of them??????
	@ 2012-12-15 6:57 AM (#9129 - in reply to #4323) (#9129) Top
chaotic_iak Posts: 241 Country : Indonesia	chaotic_iak posted @ 2012-12-15 6:57 AM sanket - 2011-05-07 9:44 PM Also the rules of hitori say that a number cannot appear more than once. So can we use the reverse rule : Circling a particular number (or shading in yellow as in above case) if its another occurence in the same row/column has been shaded (in grey color as in above) because this ensures that the number will always occur once (and cannot appear 'zero' times) ? Not necessarily. Try this: 1112 2341 1213 2421 Observe C3. Both of its 1s are shaded, leaving no 1 remaining. To above: The first is yes if the solution is guaranteed to be unique (but no otherwise), the second is no.