## Does Using Brute-Force to solve a puzzle make it invalid

Everything about Sudoku that doesn't fit in one of the other sections

### Re: Does Using Brute-Force to solve a puzzle make it invalid

rjamil wrote:setting up a list of valid candidate values at initial puzzle state and/or after each step, instead of all 1 to 9 values, will violate brute-force definition and should be called T&E / guessing algorithm.

Oh, deary me!

This is only true if you insist on a definition of "brute force" for which we have generally disagreed, as reflected in the discussion above ...

Mathimagics
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### Re: Does Using Brute-Force to solve a puzzle make it invalid

Hi MM,

Well, as per the definition of Brute-Force algorithm, search all 1 to 9 values for each empty/unsolved cell without deduct any value from unsolved cell's possible candidates/values.

Please treat my above statement for Brute-Force as 'strong opinions, weakly held'.

Since, an empty Sudoku puzzle is considered as a combination of 81 integers long password. However, there are some constraints involve, i.e., to fill a 9×9 grid with numbers so that each row, column and 3×3 box contain all of the digits between 1 and 9 only once.

Similarly, if a Sudoku puzzle has some given clues then, the remaining empty cells (i.e., 81 - given clue cells) need to be searched for all digits between 1 to 9 without applying any deduction logic.

Note that a logic is more than that a pre-defined constraint.

R. Jamil
rjamil

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Joined: 15 October 2014
Location: Karachi, Pakistan

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