static List <Coordinate_Sudoku> SolveSolution(List <Coordinate_Sudoku> Origin, List <Coordinate_Sudoku> Solution, int row, int col, int SolutionCount)
{
if (!Origin.Exists(c => c.Row == row && c.Column == col))
{
for (int value = 1; value < 10; value++)
{
Coordinate_Sudoku temp = new Coordinate_Sudoku(row, col, value, returnBlock(row, col));
if (isSafe(Origin, Solution, temp))
{
Solution.Add(temp);
if (Solution.Count < SolutionCount)
{
if (col < 9)
{
SolveSolution(Origin, Solution, row, col + 1, SolutionCount);
}
else
{
SolveSolution(Origin, Solution, row + 1, 1, SolutionCount);
}
}
if (Solution.Count < SolutionCount && Solution.Count > 0)
{
Solution.RemoveAt(Solution.Count - 1);
}
}
}
}
else
{
if (Solution.Count < SolutionCount)
{
if (col < 9)
{
SolveSolution(Origin, Solution, row, col + 1, SolutionCount);
}
else
{
SolveSolution(Origin, Solution, row + 1, 1, SolutionCount);
}
}
}
return(Solution);
}
static bool isSafe(List <Coordinate_Sudoku> Origin, List <Coordinate_Sudoku> Solution, Coordinate_Sudoku cs)
{
List <Coordinate_Sudoku> temp1 = Origin.Where(c => c.Value == cs.Value).ToList();
List <Coordinate_Sudoku> temp2 = Solution.Where(c => c.Value == cs.Value).ToList();
foreach (Coordinate_Sudoku c in temp1)
{
if (c.Row == cs.Row || c.Column == cs.Column || c.Block == cs.Block)
{
return(false);
}
}
foreach (Coordinate_Sudoku c in temp2)
{
if (c.Row == cs.Row || c.Column == cs.Column || c.Block == cs.Block)
{
return(false);
}
}
return(true);
}