как написать? про массивы)

Private Sub Command1_Click()
Dim N As Integer, i As Integer
Dim k1 As Integer, k2 As Integer, st
Dim a(), S
N = Val(InputBox("N=?", , 10))
If N < 2 Then
MsgBox "некорректный ввод"
Exit Sub
End If
ReDim a(N)
Label1 = "": Label2 = ""
For i = 1 To N
a(i) = Int(Rnd * 40) - 20
Label1 = Label1.Caption & a(i) & " , "
Next i
1
k1 = Val(InputBox("k1=?", , 1))
k2 = Val(InputBox("N=?", , 2))
If k1 > 0 And k2 > 0 And k1 <= N And k2 <= N And k1 <> k2 Then
S = 0
st = Sgn(k2 - k1)
For i = k1 To k2 Step st
S = S + a(i)
Next i
Label2 = "S = " & S
Else
MsgBox "некорректный ввод" & vbCrLf & _
"k1 не равно k2 и k1 , k2 принадлежат [" & 1 & " ; " & N & "]"
GoTo 1
End If
End Sub

Private Sub Command1_Click()
Dim a(), b(), S
Dim N As Integer, M As Integer
Dim i As Integer, j As Integer
 
N = Val(InputBox("N=?", , 5))
M = Val(InputBox("M=?", , 5))
ReDim a(N, M)
 
Text1.Text = ""
Randomize
For i = 1 To N
For j = 1 To M
a(i, j) = Int(Rnd * 71) - 40
Text1.Text = Text1.Text & a(i, j) & "  "
Next j
Text1.Text = Text1.Text & vbNewLine
Next i
 
ReDim b(2, M - 1)
Text2.Text = ""
For j = 2 To M
S = 0
b(1, j - 1) = 0
For i = 1 To j - 1
 
If a(i, j) > 0 Then
b(1, j - 1) = b(1, j - 1) + 1
S = S + a(i, j)
End If
Next i
b(2, j - 1) = S
Next j
 
 
For j = 1 To M - 1
Text2.Text = Text2.Text & "колич k = " & b(1, j) & "   сумма S = " & b(2, j) & vbCrLf
Next j
End Sub