public Task <SudokuProblem> GenerateNewProblem()
{
SudokuProblem problem = null;
// Poor man version of implementation
do
{
problem = new SudokuProblem(this.GenerateRowsRandomly());
}while (!this.ValidateProblem(problem));
return(Task.FromResult(problem));
}
public bool ValidateProblem(SudokuProblem problem)
{
if (problem == null)
{
throw new ArgumentNullException(nameof(problem));
}
var set = new HashSet <string>();
for (var i = 0; i < this.SudokuSize - 1; i++)
{
for (var j = 0; j < this.SudokuSize - 1; j++)
{
if (problem.Rows[i] != null && problem.Rows[i].Columns != null && problem.Rows[i].Columns[j] != null && problem.Rows[i].Columns[j].Value != null)
{
if (!this.isValidNumber(problem.Rows[i].Columns[j].Value))
{
// Out of range
return(false);
}
else
{
// We use a hashmap to check if the value is already existed in the current row/column/square
var rowStr = $"R{i}{problem.Rows[i].Columns[j].Value}";
var colStr = $"C{j}{problem.Rows[i].Columns[j].Value}";
var squareStr = $"S{i / Math.Sqrt(this.SudokuSize) * Math.Sqrt(this.SudokuSize) + j / Math.Sqrt(this.SudokuSize)}{ problem.Rows[i].Columns[j].Value}";
if (set.Contains(rowStr) || set.Contains(colStr) || set.Contains(squareStr))
{
return(false);
}
set.Add(rowStr);
set.Add(colStr);
set.Add(squareStr);
}
}
}
}
return(true);
}
public bool ValidateProblem([FromBody] SudokuProblem sudokuProblem)
{
return(this.sudokuService.ValidateProblem(sudokuProblem));
}
public Task <bool> Save(SudokuProblem problem)
{
return(Task.FromResult(storage.TryAdd(storage.Count, problem)));
}
