static string Run(string[] sudokuArray)
{
int row, column, index, number, maxNumberOfAttemptsToSolveSudoku = 1000, numberOfAttemptsToSolveSudoku = 0;
bool atLeastOneSimulation = false, stateHasBeenSaved = false, numbersAddedWithCertaintyAndThenNoCandidates = false;
SudokuBoard sudokuBoard = new SudokuBoard();
Candidates candidates = new Candidates();
int currentSudokuToSolve, numberOfSudokusToSolve = sudokuArray.Length;
string result = "S";
sudokuBoard.Init();
candidates.Init();
currentSudokuToSolve = 1;
while (currentSudokuToSolve <= numberOfSudokusToSolve && result == "S")
{
numberOfAttemptsToSolveSudoku = 0;
atLeastOneSimulation = false;
stateHasBeenSaved = false;
numbersAddedWithCertaintyAndThenNoCandidates = false;
sudokuBoard.SetWorkingSudokuBoard(currentSudokuToSolve - 1, sudokuArray);
candidates.SetCandidates(sudokuBoard);
while (numberOfAttemptsToSolveSudoku < maxNumberOfAttemptsToSolveSudoku && !sudokuBoard.SudokuSolved && !numbersAddedWithCertaintyAndThenNoCandidates)
{
if (numberOfAttemptsToSolveSudoku > 0)
{
sudokuBoard.RestoreState();
candidates.RestoreState();
}
while (candidates.HasCandidates)
{
number = 0;
sudokuBoard.ResetList();
while (number == 0 && sudokuBoard.NextCellInList())
{
number = candidates.TryFindNumberToSetInCellWithCertainty(sudokuBoard.CurrentRow, sudokuBoard.CurrentColumn);
}
if (number == 0)
{
candidates.SimulateOneNumber(sudokuBoard, out row, out column, out index, out number);
atLeastOneSimulation = true;
if (!stateHasBeenSaved)
{
sudokuBoard.SaveState();
candidates.SaveState();
stateHasBeenSaved = true;
}
}
else
{
row = sudokuBoard.CurrentRow;
column = sudokuBoard.CurrentColumn;
index = sudokuBoard.CurrentListIndex;
}
sudokuBoard.SetNumber(row, column, index, number);
candidates.UpdateCandidates(row, column, number);
}
if (!sudokuBoard.SudokuSolved)
{
if (!atLeastOneSimulation)
{
numbersAddedWithCertaintyAndThenNoCandidates = true;
}
else
{
sudokuBoard.CheckIfCanUpdateBestSoFarSudokuBoard();
numberOfAttemptsToSolveSudoku++;
}
}
}
result = ProcessResult(sudokuBoard, currentSudokuToSolve - 1, sudokuArray);
if ((currentSudokuToSolve % 500) == 0)
{
Console.Write("\r" + currentSudokuToSolve.ToString());
}
currentSudokuToSolve++;
}
return(result);
}
