public Board TryNextNumber()

in Sudoku/Board.cs [52:59]

• 8 lines of code
• 2 McCabe index (conditional complexity)

    public Board TryNextNumber()
    {
      GetCellToTry(out var activeRow, out var activeCol);
      var number = Cell(activeRow, activeCol).PopNextNumber();
      return number != NumberEx.Unknown 
        ? new Board(CopyCells(), activeRow, activeCol, number, _emptyCellsCount - 1)  
        : null; // we tried all numbers and all branches finished by dead end
    }