// Constructor
// filename - file from which to read the puzzle
public Sudoku(string filename)
{
// TODO: Add the following exception handling
// - Validate that the length of the first row is a perfect square value
// - Validate that each line contains the same number of elements
// - Validate that each element is a numeric value between 1 and gridSize or the unknown value
using (TextFieldParser parser = new TextFieldParser(filename))
{
int row = 0;
parser.Delimiters = new string[] { "," };
while (!parser.EndOfData)
{
// Read in a line of the puzzle
string[] parts = parser.ReadFields();
if (row == 0)
{
//Initialize the grid
gridSize = parts.Length;
subGridSize = Convert.ToInt32(Math.Sqrt(gridSize));
sudokuGrid = new NumberBlock[gridSize, gridSize];
// Initialize the range of possible block values
rangeOfValues = new List<int>(Enumerable.Range(1, gridSize).ToList());
}
// Populate the puzzle
for (var col = 0; col < gridSize; col++)
{
sudokuGrid[row, col] = new NumberBlock(row, col, subGridSize, Convert.ToInt32(parts[col]));
}
row++;
}
}
}
// Constructor
// puzzle - the sudoku puzzle to be solved
public Sudoku(int[,] puzzle)
{
// TODO: Error checking - check puzzle is actually a grid
//Initialize the grid
gridSize = puzzle.GetLength(0);
subGridSize = Convert.ToInt32(Math.Sqrt(gridSize));
sudokuGrid = new NumberBlock[gridSize, gridSize];
// Initialize the range of possible block values
rangeOfValues = new List<int>(Enumerable.Range(1, gridSize).ToList());
// Populate the grid with the data passed in
for (var row = 0; row < gridSize; row++)
for (var col = 0; col < gridSize; col++)
{
try
{
sudokuGrid[row, col] = new NumberBlock(row, col, subGridSize, puzzle[row, col]);
}
catch (Exception e)
{
// TODO: Do something more intelligent with the exception...
return;
}
}
}
public void NumberBlockConstructorSuccessful()
{
try
{
NumberBlock nb = new NumberBlock(1, 2, 3);
Assert.IsFalse(nb.ValueSet);
Assert.AreEqual(nb.PossibleValues.Count, 9);
Assert.AreEqual(nb.Row, 1);
Assert.AreEqual(nb.Column, 2);
Assert.AreEqual(nb.Grid, 0);
Assert.AreEqual(nb.RangeOfValues.Count, 9);
}
catch (NumberBlock.PositionException e)
{
Assert.Fail("Constructor should not have thrown the PositionExcpetion");
}
catch (NumberBlock.ValueException e)
{
Assert.Fail("Constructor should not have thrown the ValueException");
}
try
{
NumberBlock nb = new NumberBlock(4, 3, 3, 8);
Assert.IsTrue(nb.ValueSet);
Assert.AreEqual(nb.Value, 8);
Assert.AreEqual(nb.Row, 4);
Assert.AreEqual(nb.Column, 3);
Assert.AreEqual(nb.Grid, 4);
Assert.AreEqual(nb.PossibleValues.Count, 0);
Assert.AreEqual(nb.RangeOfValues.Count, 9);
}
catch (NumberBlock.PositionException e)
{
Assert.Fail("Constructor should not have thrown the PositionExcpetion");
}
catch (NumberBlock.ValueException e)
{
Assert.Fail("Constructor should not have thrown the ValueException");
}
}
// This method handles updating a specific block's possible values
private void UpdateBlockPossibleValues(NumberBlock block, int value)
{
var possibleVals = block.PossibleValues;
if (possibleVals.Contains(value))
{
possibleVals.Remove(value);
block.PossibleValues = possibleVals;
// If the block is now set, recurively call MarkValueAsUsed
if (block.ValueSet)
{
MarkValueAsUsed(block);
}
}
}
// This method iterated through the row, column and grid for a block that has been set
// and removes the block value from the possibleValues list of each block. This may result
// in another block being set. This method is called recursively to set subsequent blocks.
private void MarkValueAsUsed(NumberBlock block)
{
for (var col = 0; col < gridSize; col++)
{
UpdateBlockPossibleValues(sudokuGrid[block.Row, col], block.Value);
}
for (var row = 0; row < gridSize; row++)
{
UpdateBlockPossibleValues(sudokuGrid[row, block.Column], block.Value);
}
int startingRow = (block.Grid / subGridSize) * subGridSize;
int startingCol = (block.Grid % subGridSize) * subGridSize;
for (int row = startingRow; row < startingRow + subGridSize; row++)
for (int col = startingCol; col < startingCol + subGridSize; col++)
{
UpdateBlockPossibleValues(sudokuGrid[row, col], block.Value);
}
}
public void UpdatePossibleValues()
{
List<int> possibleValues = new List<int>() { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
NumberBlock nb = null;
try
{
nb = new NumberBlock(0, 0, 3);
}
catch (NumberBlock.PositionException e)
{
Assert.Fail("No exception should have been raised, PositionException raised");
}
catch (NumberBlock.ValueException e)
{
Assert.Fail("No exception should have been raised, ValueException raised");
}
Assert.IsFalse(nb.ValueSet);
Assert.AreEqual(possibleValues.Count, nb.PossibleValues.Count);
foreach (var value in nb.PossibleValues)
{
Assert.IsTrue(possibleValues.Contains(value));
}
// Only even numbers possible
possibleValues = new List<int>() { 2, 4, 6, 8 };
nb.PossibleValues = possibleValues;
Assert.AreEqual(possibleValues.Count, nb.PossibleValues.Count);
Assert.IsFalse(nb.ValueSet);
foreach (var value in nb.PossibleValues)
{
Assert.IsTrue(possibleValues.Contains(value));
}
// Only the value 6 left
possibleValues = new List<int> { 6 };
nb.PossibleValues = possibleValues;
Assert.AreEqual(nb.PossibleValues.Count, 0);
Assert.IsTrue(nb.ValueSet);
Assert.AreEqual(6, nb.Value);
}
public void NumbeBlockConstructorThrowsPositionException()
{
// Row number < 0
try
{
NumberBlock nb = new NumberBlock(-1, 0, 3, 1);
Assert.Fail("Constructor should have thown a PositionException, no exception thrown");
}
catch (NumberBlock.PositionException e)
{
// success
}
catch (NumberBlock.ValueException e)
{
Assert.Fail("Constructor should have thrown a PositionException, ValueException thrown");
}
// Row number >= 9
try
{
NumberBlock nb = new NumberBlock(9, 0, 3, 1);
Assert.Fail("Constructor should have thown a PositionException, no exception thrown");
}
catch (NumberBlock.PositionException e)
{
// success
}
catch (NumberBlock.ValueException e)
{
Assert.Fail("Constructor should have thrown a PositionException, ValueException thrown");
}
// Column number < 0
try
{
NumberBlock nb = new NumberBlock(0, -1, 3, 1);
Assert.Fail("Constructor should have thown a PositionException, no exception thrown");
}
catch (NumberBlock.PositionException e)
{
// success
}
catch (NumberBlock.ValueException e)
{
Assert.Fail("Constructor should have thrown a PositionException, ValueException thrown");
}
// Column number >= 9
try
{
NumberBlock nb = new NumberBlock(0, 9, 3, 1);
Assert.Fail("Constructor should have thown a PositionException, no exception thrown");
}
catch (NumberBlock.PositionException e)
{
// success
}
catch (NumberBlock.ValueException e)
{
Assert.Fail("Constructor should have thrown a PositionException, ValueException thrown");
}
}
public void NumberBlockConstructorThrowsValueException()
{
// Value < -1
try
{
NumberBlock nb = new NumberBlock(0, 0, 2, -3);
}
catch (NumberBlock.ValueException e)
{
// success
}
catch (NumberBlock.PositionException e)
{
Assert.Fail("Constructor should have thrown a ValueException, PositionException thrown");
}
// Value > 9
try
{
NumberBlock nb = new NumberBlock(0, 0, 4, 10);
}
catch (NumberBlock.ValueException e)
{
// success
}
catch (NumberBlock.PositionException e)
{
Assert.Fail("Constructor should have thrown a ValueException, PositionException thrown");
}
}