Question

用递归算法编写求斐波那契数列前n项和的程序

用function定义函数

Answer 1

Private Function F(n As Long) As Long
If n > 2 Then
F = F(n - 1) + F(n - 2)
Else
F = 1
End If
End Function

Private Sub Command1_Click()
Dim a As String
Dim i as long
Dim n as long
Dim sum as long
a = InputBox("输入斐波那契数列项数", "输入")
n = Clng(a)
Cls
For i=1 to n
sum = sum + F(i)
Next

Print "斐波那契数列前";Cstr(n);"项和：";sum
End Sub