Problem 114. Check to see if a Sudoku Puzzle is Solved

Created by @bmtran (Bryant Tran)

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Description:Your task, should you choose to accept it, is to make a function that checks to see if a 9x9 matrix of integers represents a completed sudoku puzzle. For more information regarding sudokus, refer to the <a href="http://en.wikipedia.org/wiki/Sudoku">wikipedia page</a>.The function will return true only when it's a completed sudoku puzzle. A value of 0 refers to a blank entry.Example:<pre> input = [ 8 2 4 9 5 3 6 7 1
 6 3 5 8 1 7 9 2 4
 7 1 9 6 2 4 8 5 3
 5 8 7 2 9 1 3 4 6
 1 4 2 7 3 6 5 8 9
 3 9 6 4 8 5 2 1 7
 2 6 1 5 4 9 7 3 8
 4 7 8 3 6 2 1 9 5
 9 5 3 1 7 8 4 6 2 ];
 answer = true;</pre><pre> input = [ 8 2 4 9 5 3 6 7 1
 6 3 5 8 1 7 9 2 4
 7 1 9 0 2 4 8 5 3
 5 8 7 2 9 1 3 4 6
 1 4 2 7 3 0 5 8 9
 3 9 6 4 8 5 2 1 7
 2 6 1 5 4 9 7 3 8
 4 7 8 3 6 2 1 9 5
 9 5 3 1 7 8 4 6 2 ];
 answer = false;</pre>

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Last Solution submitted on May 03, 2023

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@bmtran (Bryant Tran) on 28 Jan 2012

Seems like my test suite wasn't robust enough, so I've bolstered it with some trickier situations

yurenchu on 26 May 2017

You should have added a test case with 5*ones(9) as a test matrix.

Asif Newaz on 13 Nov 2019

ur test suite 6 is wrong, isn't it??

Dyuman Joshi on 26 Dec 2020

@bmtran can you explain why test case #6 (toeplitz variation) is false?

@bmtran (Bryant Tran) on 26 Dec 2020

In addition to each row and column needing to have 1 through 9, each 3x3 sub-region must have 1 through 9 as well.

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Problem 114. Check to see if a Sudoku Puzzle is Solved

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Problem 114. Check to see if a Sudoku Puzzle is Solved

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