Осуществить циклический сдвиг элементов массива на m позиций влево

Sub nn()
st = "Исходный массив" + Chr(13)
 Randomize
 n = InputBox("Введите количество элементов")
 ReDim a(1 To n) As Integer
 For i = 1 To n
   a(i) = Int(Rnd * 10)
   st = st + Str(a(i)) + "  "
Next i
  MsgBox st
  k = InputBox("На сколько позиций сдвинуть влево")
  For i = 1 To k
     For j = 1 To n
    If j = 1 Then
     r = a(j)
    Else
     a(j - 1) = a(j)
    End If
  Next j
   a(n) = r
  Next i
  st = st + Chr(13) + "Сдвинутый массив" + Chr(13)
For i = 1 To n
 st = st + Str(a(i)) + "  "
Next i
 MsgBox (st)
End Sub

Private Sub CommandButton1_Click()
Dim n As Integer, m As Integer, i As Integer, j As Integer, k As Integer, z As Integer, d As Integer
n = InputBox("Введите кол-во строк", "", "7")
m = InputBox("Введите кол-во стобцов", "", "5")
k = 1: i = 1: j = 1
z = 1: d = 1
q = n * m + 1
Do While (k < q)
 
 
If z = 1 Then
If j < m Then
Cells(i + 1, j + 1) = k
j = j + 1
Else
z = 2
End If
End If
If z = 2 Then
If i < n Then
Cells(i + 1, j + 1) = k
i = i + 1
 
Else
z = 3
'd = d + 1
End If
End If
If z = 3 Then
If j >= d Then
Cells(i + 1, j + 1) = k
j = j - 1
Else
z = 4
i = i - 1
j = j + 1
d = d + 1
End If
End If
If z = 4 Then
If i > d Then
 
Cells(i + 1, j + 1) = k
i = i - 1
Else
Cells(i + 1, j + 1) = k
z = 1
n = n - 1
m = m - 1
j = j + 1
 
End If
End If
k = k + 1
Loop
End Sub