public void GivenAnExampleEulerBoard()
{
var input = new string[]
{
"..3.2.6..",
"9..3.5..1",
"..18.64..",
"..81.29..",
"7.......8",
"..67.82..",
"..26.95..",
"8..2.3..9",
"..5.1.3..",
};
_board = FromStringArray(input);
}
public void GivenADifficultBoard()
{
var input = new string[]
{
"...5...6.",
"8.9....1.",
"16..87...",
"3...26...",
"..7.1.6..",
"...85...3",
"...47..21",
".4....9.8",
".8...3..."
};
_board = FromStringArray(input);
}
/// <summary>
/// Checks if the move is valid. A move is NOT valid if:
/// * the square is read only
/// * the row already contains the number
/// * the column already contains the number
/// * the 3x3 group already contains the number
/// </summary>
/// <returns>Returns true if it is a valid move.</returns>
private bool IsAValidMove(Board board, int row, int col, int number)
{
//Not valid move if readonly
if (board.Squares[row, col].ReadOnly)
return false;
//Not valid move if row contains number
for (var i = 0; i < board.Size; i++)
{
if (i != col && board.Squares[row, i].Number == number)
{
return false;
}
}
//Not valid move if col contains number
for (var i = 0; i < board.Size; i++)
{
if (i != row && board.Squares[i, col].Number == number)
{
return false;
}
}
//Not valid move if group contains number
var box = GetBox(row, col);
var rows = 0;
var cols = 0;
if (box >= 3 && box < 6)
rows = 3;
else if (box >= 6 && box < 9)
rows = 6;
if (box == 1 || box == 4 || box == 7)
cols = 3;
else if (box == 2 || box == 5 || box == 8)
cols = 6;
for (var i = rows; i < rows + 3; i++)
{
for (var j = cols; j < cols + 3; j++)
{
if (board.Squares[i, j].Number == number)
return false;
}
}
return true;
}
/// <summary>
/// Finds an emtpy square of the board, of any.
/// </summary>
/// <param name="board">The board.</param>
/// <param name="row">Output parameter row of the empty square. -1 if no empty square left.</param>
/// <param name="col">Output parameter col of the empty square. -1 if no empty square left.</param>
private void FindEmptySquare(Board board, out int row, out int col)
{
row = -1;
col = -1;
for (int i = 0; i < board.Size; i++)
{
if (row > -1)
break;
for (int j = 0; j < board.Size; j++)
{
if (board.Squares[i, j].Number == 0)
{
row = i;
col = j;
break;
}
}
}
}
/// <summary>
/// Solves the sudoku.
/// </summary>
/// <returns>Returns true if the game is solvable.</returns>
public bool Solve(Board board)
{
int row;
int col;
FindEmptySquare(board, out row, out col);
if (row < 0 && col < 0)
return true;
for (int i = 1; i < 10; i++)
{
if (Move(board, row, col, i))
{
if (Solve(board))
return true;
// Can't find a valid number, reset number to zero and continue.
board.Squares[row, col].SetNumber(0);
}
}
return false;
}
/// <summary>
/// Makes a move on given board.
/// </summary>
/// <returns>Returns true if the move was made. Returns false if the move
/// was not made (i.e. invalid move).</returns>
public bool Move(Board board, int row, int col, int number)
{
// Check if index is outside board
if (row < 0 || row >= board.Size || col < 0 || col >= board.Size)
{
return false;
}
// Check if valid move
if (!IsAValidMove(board, row, col, number))
return false;
board.Squares[row, col].SetNumber(number);
return true;
}
public void SetUp()
{
_board = new Board(Content);
}
public void Board_should_have_medium_classification()
{
var mediumBoard = new Board(MediumContent);
Assert.AreEqual(Classification.Medium, mediumBoard.Classification);
}
public void Board_should_have_easy_classification()
{
var easyBoard = new Board(EasyContent);
Assert.AreEqual(Classification.Easy, easyBoard.Classification);
}
public void SetUp()
{
var content = "510000083800416005000000000098504610000901000064203570000000000600157004780000096";
_board = new Board(content);
_gameEngine = new GameEngine();
}
public void GivenThisBoard(string input)
{
_board = ParseInput(input);
}
public void GivenAnEmptyBoard()
{
_board = Board.Empty;
}
public void WhenDigitPlacedAtRowCol(int digit, int row, int col)
{
//TODO: implement act (action) logic
_board = _board.Play(digit, row, col);
}
public void TheSolverMakesTheRequiredMoves()
{
_solver = _solver.MakeRequiredMoves();
_board = _solver.Board;
Debug.WriteLine("Board after required moves made:\n" + Printer.Print(_board));
}
