求 vb编程 3个数中 最大公约数 代码

Private Function maxgongyueshu(a, b)
Dim min, max, i As Long
If a <= b Then
min = a: max = b
Else: min = b: max = a
End If
i = max Mod min
If i = 0 Then
maxgongyueshu = min
Exit Function
End If
Do Until a Mod i = 0 And b Mod i = 0
i = max Mod min
max = min
min = i
Loop
maxgongyueshu = i
End Function

Private Sub Form_Load()
Dim a, b, c As Long
a = InputBox("a=")
b = InputBox("b=")
c = InputBox("c=")
a = maxgongyueshu(a, b)
a = maxgongyueshu(a, c)
MsgBox a
End Sub

Private Sub Command1_Click()

Dim a%, b%, c%
a = Val(Text1.Text)
b = Val(Text2.Text)
c = Val(Text3.Text)
f = gcd(a, b)
Text4.Text = gcd(c, f)
End Sub
Public Function gcd(ByVal m%, ByVal n%) As Integer
If m < n Then t = m: m = n: n = t
r = m Mod n
Do While (r <> 0)