有一個分數序列

求出這個數列的前20項之和。

代碼1

Private Sub Command1_Click()
    Dim sum As Double
    Dim a As Integer, b As Integer, t As Integer
    a = 1
    b = 2
    sum = 0
    For i = 1 To 20
        sum = sum + b / a
        t = a + b
        a = b
        b = t
    Next i
    Label2.Caption = Str(sum)
End Sub

代碼2

Private Sub Command1_Click()
    Dim sum As Double
    Dim a As Integer, b As Integer, t As Integer
    a = 1
    b = 2
    sum = b / a
    For i = 2 To 20
        t = a + b
        a = b
        b = t
	sum = sum + b / a
    Next i
    Label2.Caption = Str(sum)
End Sub

分數序列【VB代碼實現】