Private Sub Command1_Click()

 Dim y As Integer

 y = Val(Text1.Text)

 Label1.Caption = Str(f(y))

End Sub

Function f(n As Integer) As Integer

 If (n = 1) Or (n = 2) Then

    f = 1

  Else

    f = f(n - 1) + f(n - 2)

  End If

End Function

程序运行时，在文本框中输入8，单击命令按钮Command1后，Label1中显示的内容是：

现要求编写VB程序（运行界面图所示），实现如下功能：在文本框Text1中输入一个三位数整数，单击“求解”按钮Command1，在文本框Text2中显示重新组合后的最大三位数整数。某同学按此要求编写的程序如下，其中函数max(x)用于求解最大三位数整数，但加框处代码有错，请改正。

①{#blank#}1{#/blank#}      ②{#blank#}2{#/blank#}

Function max(x As Integer) As Integer

  Dim a As Integer, b As Integer, c As Integer, t As Integer

  a = x \ 100

  b = (x \ 10) \ 10             ' ①

  c = x mod 10

  If a < b Then t = a: a = b: b = t

  If a < c Then t = a: a = c: c = t

  If b < c Then t = c: c = b: b = t

  max = c* 100 + b * 10 + a     ' ②

End Function

Private Sub Command1_Click()

     Dim n As Integer, y As Integer

     n = Val(Text1.Text)

     y = max(n)

     Text2.Text = Str(y)

End Sub

Dim a(1 to 5) as integer, i as integer, c as integer

a(1)=2: a(2)=1: a(3)=3: a(4)=4: a(5)=5

c=0

for i=3 to 5

 if a(i-2)+a(i-1) =a(i) then c=c+1

next i

text1.text = str(c)

该程序运行后，文本框text1中显示的内容是（   ）

       a(i)=i+1

    Next i

程序运行后，变量i的值是：（   ）

引起该错误的原因是（  ）