internal SudokuSolutionNode Step(SudokuSolutionNode a_node, SudokuSolutionType a_type)
{
if (a_node.Board.IsEmpty)
{
return(new SudokuSolutionNode(a_node.Board, SudokuSolutionNodeState.Unsolvable));
}
if (a_node.StepMode != SudokuSolutionNodeStepMode.StepAllAlgorithms)
{
Debug.Assert(!a_node.Nodes.Any());
a_node.StepMode = SudokuSolutionNodeStepMode.StepSelectedAlgorithm;
List <SudokuSolution> solution_nodes = SudokuSolutionTypeToSolvingFunction(a_type)(a_node.NextBoard, true);
solution_nodes = SudokuSolutionNode.Consolidate(solution_nodes.Distinct().ToList());
foreach (SudokuSolution solution in solution_nodes)
{
if (!a_node.Nodes.Any(n => n.Solution.Equals(solution)))
{
a_node.AddNode(a_node.NextBoard, SudokuSolutionNodeState.Solution, solution);
}
}
}
return(a_node.Nodes.FirstOrDefault(node => node.Solution.Type == a_type));
}
private static void LoadNodesFromXML(XElement a_element, SudokuSolutionNode a_parent)
{
a_element.Element("solution_nodes").Elements().ForEach(child_element =>
{
SudokuBoard board = SudokuBoard.LoadFromXML(child_element.Element("board"));
SudokuSolutionNode child_node = a_parent.AddNode(
board,
(SudokuSolutionNodeState)Enum.Parse(typeof(SudokuSolutionNodeState), child_element.Attribute("state").Value),
SudokuSolution.LoadFromXML(child_element.Element("solution"), board)
);
LoadNodesFromXML(child_element, child_node);
});
}
internal SudokuSolutionNode Step(SudokuSolutionNode a_node)
{
if (a_node.Board.IsEmpty)
{
return(new SudokuSolutionNode(a_node.Board, SudokuSolutionNodeState.Unsolvable));
}
if ((a_node.StepMode != SudokuSolutionNodeStepMode.StepFirstSolution) &&
(a_node.StepMode != SudokuSolutionNodeStepMode.StepAllAlgorithms))
{
a_node.StepMode = SudokuSolutionNodeStepMode.StepFirstSolution;
if (a_node.State == SudokuSolutionNodeState.State)
{
List <SudokuSolution> solutions = null;
if (a_node.NextBoard.IsSolvable)
{
// PLINQ
solutions = (from func in m_simple_funcs.Concat(m_complex_funcs)
select func(a_node.NextBoard, false)).FirstOrDefault(sols => sols.Count > 0);
}
if (solutions != null)
{
solutions = SudokuSolutionNode.Consolidate(RemoveOverlapped(solutions.Distinct().ToList()));
if (solutions.Count == 0)
{
solutions = null;
}
}
if (solutions != null)
{
foreach (SudokuSolution solution in solutions)
{
SudokuSolutionNode node = a_node.AddNode(a_node.NextBoard, SudokuSolutionNodeState.Solution, solution);
node = node.AddNode(node.NextBoard, SudokuSolutionNodeState.State);
UpdateState(node, false);
}
a_node = a_node.Nodes.First().Nodes.First();
}
else
{
UpdateState(a_node, true);
}
}
else
{
a_node = a_node.AddNode(a_node.NextBoard, SudokuSolutionNodeState.State);
UpdateState(a_node, false);
}
}
else
{
if (a_node.Nodes.Any())
{
a_node = a_node.Nodes.First();
}
else
{
UpdateState(a_node, true);
}
}
return(a_node);
}
internal void StepAll(SudokuSolutionNode a_node)
{
if (a_node.StepMode == SudokuSolutionNodeStepMode.StepAllAlgorithms)
{
return;
}
a_node.StepMode = SudokuSolutionNodeStepMode.StepAllAlgorithms;
if ((a_node.State == SudokuSolutionNodeState.Solved) ||
(a_node.State == SudokuSolutionNodeState.Unsolvable) ||
(a_node.State == SudokuSolutionNodeState.Unsolved))
{
return;
}
if (a_node.Board.IsEmpty)
{
return;
}
if (a_node.State == SudokuSolutionNodeState.Solution)
{
if (!a_node.Nodes.Any())
{
a_node = a_node.AddNode(a_node.NextBoard, SudokuSolutionNodeState.State);
UpdateState(a_node, false);
}
}
else
{
ConcurrentBag <SudokuSolution> solution_nodes = new ConcurrentBag <SudokuSolution>();
Parallel.ForEach(m_simple_funcs, func =>
{
List <SudokuSolution> list = func(a_node.NextBoard, true);
foreach (var sol in list)
{
solution_nodes.Add(sol);
}
});
if (solution_nodes.Count == 0)
{
Parallel.ForEach(m_complex_funcs, func =>
{
List <SudokuSolution> list = func(a_node.NextBoard, true);
foreach (var sol in list)
{
solution_nodes.Add(sol);
}
});
}
List <SudokuSolution> solution_nodes_1 = SudokuSolutionNode.Consolidate(solution_nodes.Distinct().ToList());
foreach (SudokuSolution solution in solution_nodes_1)
{
if (!a_node.Nodes.Any(n => n.Solution.Equals(solution)))
{
a_node.AddNode(a_node.NextBoard, SudokuSolutionNodeState.Solution, solution);
}
}
}
}
