/// <summary>
/// Make New Sudoku Grid
/// </summary>
/// <returns></returns>
public int[,] Make()
{
_Grid = new int[_GridNum, _GridNum];
for (int i = 0; i < _GridNum / _BoxNum; i++) {
int row = i*_BoxNum;
int[] nums = new int[_GridNum];
nums = RandomMethods.UniqueRange(1, _GridNum+1);
for (int j = 0; j < _BoxNum; j++)
{
for (int k = 0; k < _BoxNum; k++)
{
_Grid[row + j, row + k] = nums[j * _BoxNum + k];
}
}
}
if (_Solve(_Grid))
{
return _Grid;
}
else
{
return null;
}
;
}
/// <summary>
/// Remove K amount of places from grid.
/// </summary>
/// <param name="K"></param>
/// <param name="grid"></param>
/// <returns></returns>
public int[,] RemoveKPlaces(int K,int[,] grid) {
if (grid == null) { return null; }
int[] nums = new int[_GridNum * _GridNum];
nums = RandomMethods.UniqueRange(0, nums.Length);
for (int i = 0; i < K; i++)
{
int row = nums[i] / _GridNum;
int col = nums[i] % _GridNum;
grid[row, col] = 0;
}
return grid;
}