/// <summary>
/// Solve sudoku by Brute Force (recursively).
///
/// Algorithm:
/// Create object of internal class SudokuNode as a root of recursive method.If the sudoku is not wrong call
/// 'solve' method the root object.
/// </summary>
/// <param name="sudoku">Sudoku object to solve.</param>
/// <param name="solveOne">Parameter to enable finishing function after writing one value to a cell.</param>
/// <returns>True if sudoku was solved. Otherwise False.</returns>
public override bool Solve(Sudoku sudoku, bool solveOne = false)
{
_Root = new SudokuNode(sudoku);
SudokuNode.SudokuSolved = null;
if (!sudoku.IsWrong())
{
_Root.Solve();
if (SudokuNode.SudokuSolved != null)
{
sudoku.CopyFrom(SudokuNode.SudokuSolved);
return(true);
}
}
return(false);
}
public bool InitializeGrid(TextBox[,] textBoxes, Label statusLabel, Label timeLabel) //Return true if everything is ok, false if error
{
stopwatch.Restart();
statusText = statusLabel;
timeText = timeLabel;
statusText.Text = "Initializing";
for (int x = 0; x < 9; x++) //Setup the 2d grid from text boxes nad check for errors
{
for (int y = 0; y < 9; y++)
{
int u = 0;
if (Int32.TryParse(textBoxes[x, y].Text, out u))
{
if (u < 0 || u > 9) //Found an invalid number
{
textBoxes[x, y].BackColor = System.Drawing.Color.Red;
statusText.Text = "Error";
stopwatch.Stop();
return(false);
}
else
{
nodeArray[x, y] = new SudokuNode(u, x, y);
}
}
else
{
nodeArray[x, y] = new SudokuNode(0, x, y);
}
}
}
StartSolving();
return(true);
}
public bool StartBruteForcing()
{
SudokuNode[,] bruteForceArray = new SudokuNode[9, 9];
bruteForceArray = nodeArray;
List <SudokuNode> emptyNodes = new List <SudokuNode>();
for (int y = 0; y < 9; y++) //Get all empty nodes that need to be publicated
{
for (int x = 0; x < 9; x++)
{
if (bruteForceArray[x, y].nodeNumber == 0)
{
emptyNodes.Add(bruteForceArray[x, y]);
}
}
}
bool end = false;
int lastCahngedIndex = -1;
while (!end) //Bruteforcing loop
{
if (lastCahngedIndex == emptyNodes.Count - 1)
{
end = true;
}
else
{
lastCahngedIndex++;
bool foundANumber = false;
for (int i = emptyNodes[lastCahngedIndex].nodeNumber + 1; i < 10; i++) //Increment the thing by minimum amount
{
if (i != 0)
{
if (CanSetHere(emptyNodes[lastCahngedIndex].positionX, emptyNodes[lastCahngedIndex].positionY, i, bruteForceArray))
{
emptyNodes[lastCahngedIndex].nodeNumber = i;
foundANumber = true;
break;
}
}
}
if (!foundANumber) //Didnt find a number, backtrack and change others
{
emptyNodes[lastCahngedIndex].nodeNumber = 0;
lastCahngedIndex -= 2;
}
}
}
if (SudokuSolved(bruteForceArray)) //If solved
{
nodeArray = bruteForceArray;
return(true);
}
else //Not solved
{
return(false);
}
}
