Sudoku Generate

Do While count < 81
count = 0
For i As Integer = 0 To 8
For j As Integer = 0 To 8
xy(i, j) = 0
Next
Next
For i As Integer = 1 To 9 ' Number loop
For index As Integer = 1 To 9
x(index) = False
y(index) = False
Next
For j As Integer = 1 To 3 'Block loop
For k As Integer = 1 To 3 'Block loop
lx = (j - 1) * 3 + rd.Next(1, 3)
ly = (k - 1) * 3 + rd.Next(1, 3)
Do While Not (xy(lx - 1, ly - 1) = 0 And x(lx) = False And y(ly) = False)
For j1 As Integer = 3 To 1 Step -1
For k1 As Integer = 3 To 1 Step -1
lx = j1 + +(j - 1) * 3
ly = k1 + (k - 1) * 3
If (xy(lx - 1, ly - 1) = 0 And x(lx) = False And y(ly) = False) Then
Exit Do
End If
Next
Next
i = 10
k = 4
j = 4
Exit Do
Loop
'Find it, set value
If xy(lx - 1, ly - 1) = 0 And x(lx) = False And y(ly) = False Then
xy(lx - 1, ly - 1) = i
x(lx) = True
y(ly) = True
count = count + 1
End If
Next
Next
Next
Loop