下列说法中，正确的是（ ）
Private Sub Command1_Click()
Dim n As Integer， ans As Integer
n = 5
Dim x(1 To 5) As Integer
x(1) = -30: x(2) = 26: x(3) = -18: x(4) = 60: x(5) = 22
ans = 60
For i = 1 To n
If x(i) < 0 Then x(i) = -x(i)
ans = ans + gcd(ans， x(i))
Next i
Text1.Text = Str(ans)
End Sub
Function gcd(a As Integer， b As Integer)
If b = 0 Then
gcd = a
Else
gcd = gcd(b， a Mod b)
End If
End Function
执行该程序段后，Text1. Text中显示的值为（ ）
Private Sub Command1_Click()
For i = 2 To n
If a(i) > a(i-1) Then ①
Next i
Text1.Text = ②
End Sub
下列选项中，①②中的代码填写正确的是（ ）
Private Sub Command1_Click()
Dim key As Integer， i As Integer， j As Integer， ans As Integer
Dim n As Integer
n = 10
Dim x(1 To 10) As Integer
x(1) = 5 : x(2) = 52 : x(3) = 2 : x(4) = 72 : x(5) = 86
x(6) = 3256 : x(7) = 123 : x(8) = 25 : x(9) = 30 : x(10) = 87
key = Val(Text1.Text)
i = 1 : j = n : ans = 0
Do While i < j
m = (i + j + 1) \ 2
If key <= x(m) Then
j = m - 1 : ans = ans + 1
Else
i = m + 1 : ans = ans + 2
End If
Loop
End Sub
在Text1中输入3256，单击Command1，程序运行完毕后，以下变量的值不正确的是（ ）
B . 
C . 
D . 
请回答下列问题：
Const maxn = 500005
Dim n As Long， a As Long， b As Long
Dim f(1 To maxn) As Long
Dim i As Long， tby As Long
Private Sub Command1_Click()
tby = 1
n = Val(Text1.Text) : a = Val(Text2.Text) : b = Val(Text3.Text)
For i = 1 To n
f(i) = Getin()
Next i
Dim l As Long， r As Long， m As Long
l = 0: r = n
Do While l <= r
m = (l + r) / 2
If Then
r = m - 1
Else
l = m + 1
End If
Loop
Label1.Caption = Str(r + 1)
End Sub
Function check(x As Long)
Dim y As Long
y = x
For i = 1 To n
Dim tmp As Long
If tmp > 0 Then 
If y < 0 Then
check = True
Exit Function
End If
Next i
check = False
End Function
Function Getin() As Long
Dim aaa As String
aaa = Mid(Text4.Text， tby， 1)
If aaa = " " Then tby = tby + 1
aaa = Mid(Text4.Text， tby， 1)
Dim bbb As Long
bbb = 0
Do While aaa <> " " And tby <= Len(Text4.Text)
bbb = bbb * 10 + Val(aaa) : tby = tby + 1
aaa = Mid(Text4.Text， tby， 1)
Loop
Getin = bbb
End Function
一共有n（3<=n<=100）个学校，各所学校之间的线路长度以一行共n*n个数据输入，
第i组的n个数据为从第i个学校出发到其他学校的线路长度，保证第i组的第i个数据为0。
编写VB程序，实现上述功能。运行程序，在文本框Text1中输入学校总数，
在文本框Text2中按题述方法输入各校之间的距离，点击命令按钮Command1后，在标签Label1中显示最短的线路总长。程序运行界面如图所示。
请回答下列问题：
Const INF = 2147483646
Dim n As Long， a As Long
Dim dis(1 To 10001) As Long， flag(1 To 10001) As Boolean
Dim head(1 To 10001) As Long， nxt(1 To 10001) As Long
Dim ed(1 To 10001) As Long， value(1 To 10001) As Long
Dim cnt As Long， tby As Long， sss As String
Dim i As Long， j As Long
Private Sub Command1_Click()
cnt = 0
n = Val(Text1.Text)
For i = 1 To n
dis(i) = INF : flag(i) = False : head(i) = 0
Next i
tby = 1
sss = Text2.Text
For i = 1 To n
For j = 1 To n
If i <> j Then Call addedge(i， j， a)
Next j
Next i
Dim ans As Long
dis(1) = 0 : ans = 0
For i = 1 To n
Dim hg As Long， u As Long
hg = INF
u = 0
For j = 1 To n
If Then
hg = dis(j)
u = j
End If
Next j
flag(u) = True
Dim p As Long
p = head(u)
Do While p <> 0
Dim v As Long
v = ed(p)
If Not flag(v) And dis(v) > value(p) Then
dis(v) = value(p)
End If
p = nxt(p)
Loop
Next i
Label1.Caption = Str(ans)
End Sub
Sub addedge(a As Long， b As Long， x As Long)
cnt = cnt + 1
value(cnt) = x
ed(cnt) = b
nxt(cnt) = head(a)
head(a) = cnt
End Sub
Function Getin() As Long
Dim aaa As String
aaa = Mid(sss， tby， 1)
If aaa = " " Then tby = tby + 1
aaa = Mid(sss， tby， 1)
Dim bbb As Long
bbb = 0
Do While aaa <> " " And tby <= Len(sss)
bbb = bbb * 10 + Val(aaa) : tby = tby + 1
aaa = Mid(sss， tby， 1)
Loop
Getin = bbb
End Function
