Дан массив из N чисел. Сформировать из него два массива

dim a1() 'чет
dim a2() 'нечет
redim a1(0 to (N-1)\2)
redim a2(0 to (N-2)\2)
for i=0 to N-1
  if i mod 2 = 0 then
    a1=a(i)
  else
    a2=a(i)
  end if
next i

dim a1 'чет
dim a2 'нечет
for i=0 to N-1
  if a(i) mod 2 = 0 then
    a1=a1 & a(i) & " "
  else
    a2=a2 & a(i) & " "
  end if
next i
a1=Split(trim(a1), ",")
a2=Split(trim(a2), ",")

Private Sub Command1_Click()
Dim a() As Single
Dim b() As Single
Dim c() As Single
Dim nA, nB, nC
nA = InputBox("kol-vo elementov")
ReDim a(1 To nA) As Single
For i = 1 To nA
a(i) = InputBox(i)
Next i
nB = 0
nC = 0
For i = 1 To nA
If (a(i) Mod 2 = 0) Then
nB = nB + 1
ReDim Preserve b(1 To nB) As Single
b(nB) = a(i)
Else
nC = nC + 1
ReDim Preserve c(1 To nC) As Single
c(nC) = a(i)
End If
Next i
For i = 1 To nB
MsgBox (b(i))
Next i
For i = 1 To nC
MsgBox (c(i))
Next i
End Sub

bbb = ""
For i = 1 To nB
bbb = bbb & " " & b(i)
Next i
MsgBox (bbb)
ccc = ""
For i = 1 To nC
ccc = ccc & " " & c(i)
Next i
MsgBox (ccc)

a = Array(1, 2, 3, 4, 5, 7, 9, 11, 13, 15, 17, 19)
N = 12
Dim a1 'чет
Dim a2 'нечет
For i = 0 To N - 1
  If a(i) Mod 2 = 0 Then
    a1 = a1 & a(i) & " "
  Else
    a2 = a2 & a(i) & " "
  End If
Next i
a1 = Split(Trim(a1), ",")
a2 = Split(Trim(a2), ",")