斐波那契数列第1项是0，第二项是1，以后各项都是前两的和，VB，求第N项的值 请帮修改，谢谢呀！ Function

这样？

Function fun(x As Integer) As Integer
Dim a As Integer, b As Integer, c As Integer, n As Integer
a = 1
b = 1
c = 0
For n = 3 To x
c = a + b
a = b
b = c
Next
Return c
End Function

Private Sub Form_Click()
Dim n As Integer
n = InputBox("")
Print fun(n)
End Sub

Function fun(x As Integer) As Integer
a = 0
b = 1
For n = 3 To x
c = a + b
a = b
b = c
Next n
fun = c
End Function

Private Sub Form_Click()
Dim n As Integer
n = Val(InputBox(""))
Print fun(n)

End Sub

你这个是正确的！
n = 2
可以不要，放在哪里也不影响结果！