So sánh các số

[blueman2]

Dim i As Long
Dim arr1(), arr2(), arr3(), arr4(), tong, tong1, trungbinh2, trungbinh3, trungbinh4, RSFE As Double
Dim n As Integer
ReDim arr1(SolieudubaoDataGridView.Rows.Count - 1)
ReDim arr2(SolieudubaoDataGridView.Rows.Count - 2)
ReDim arr3(SolieudubaoDataGridView.Rows.Count - 2)
ReDim arr4(SolieudubaoDataGridView.Rows.Count - 2)
For i = 0 To SolieudubaoDataGridView.Rows.Count - 2
arr1(i) = Me.SolieudubaoDataGridView.Rows(i).Cells(2).Value
Next i
Select Case n
Case Is = 2
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
arr2(i) = (arr1(i) + arr1(i + 1)) / 2
Next i
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
arr3(i) = Math.Abs(arr1(i + 2) - arr2(i))
Next i
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
arr4(i) = arr1(i + 2) - arr2(i)
Next i
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
tong = arr3(i) + tong
trungbinh2 = tong / (SolieudubaoDataGridView.Rows.Count - 3)
tong1 = arr4(i) + tong1
RSFE = tong1 / trungbinh2
RSFE = Math.Round(RSFE, 2)
Next i
Case Is = 3
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
arr2(i) = (arr1(i) + arr1(i + 1)) / 3
Next i
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
arr3(i) = Math.Abs(arr1(i + 2) - arr2(i))
Next i
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
arr4(i) = arr1(i + 2) - arr2(i)
Next i
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
tong = arr3(i) + tong
trungbinh3 = tong / (SolieudubaoDataGridView.Rows.Count - 3)
tong1 = arr4(i) + tong1
RSFE = tong1 / trungbinh3
RSFE = Math.Round(RSFE, 2)
Next i
Case Else
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
arr2(i) = (arr1(i) + arr1(i + 1)) / 4
Next i
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
arr3(i) = Math.Abs(arr1(i + 2) - arr2(i))
Next i
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
arr4(i) = arr1(i + 2) - arr2(i)
Next i
For i = 0 To SolieudubaoDataGridView.Rows.Count - 4
tong = arr3(i) + tong
trungbinh4 = tong / (SolieudubaoDataGridView.Rows.Count - 3)
tong1 = arr4(i) + tong1
RSFE = tong1 / trungbinh4
RSFE = Math.Round(RSFE, 2)
Next i
End Select

Mình muốn n tự chạy trong các trường hợp n=2,n=3,n=4. Sau khi chạy xong thì nó sẽ chọn giá trị min trong các giá trị trungbinh2,trungbinh3,trungbinh4 ở các trường hợp, xuất ra 1 textbox Vậy mình cần phải làm gì nữa. Các bác giúp dùm!!