Various location for Dim...

[alee001]

I write 4 code as follow to solve LCM/GCL but I don't know reason why the answer is wrong with various location on Dim r as Integer?

[FONT=Courier New]Dim m As Integer
 Dim n As Integer
 Dim r As Integer   'location 1
 Sub GCD(m, n)
 r = m Mod n
 If r = 0 Then
 MsgBox n & " is GCD"  'Wrong ans.
Else
 Call GCD(n, r)
 End If
 End Sub

 Private Sub CommandButton1_Click()
 m = InputBox("Input an interger m ")
 n = InputBox("Input an interger n")
 Call GCD(m, n)
 End Sub[/FONT]

[FONT=Courier New][FONT=Courier New]Dim m As Integer
 Dim n As Integer
 Sub GCD(m, n)
 Dim r As Integer   [FONT=Courier New]'location 2[/FONT]
 r = m Mod n
 If r = 0 Then
 MsgBox n & " is GCD" 'Correct ans.
Else
 Call GCD(n, r)
 End If
 End Sub[/FONT]

Private Sub CommandButton1_Click()
 m = InputBox("Input an interger m ")
 n = InputBox("Input an interger n")
 Call GCD(m, n)
 End Sub[/FONT]

[FONT=Courier New]Dim m As Integer
 Dim n As Integer
 Sub GCD(m, n)
 r = m Mod n
 If r = 0 Then
 MsgBox n & " is GCD"   'Correct ans.
 Else
 Call GCD(n, r)
 End If
 End Sub

 Private Sub CommandButton1_Click()
 Dim r As Integer   [FONT=Courier New]'location 3[/FONT]
 m = InputBox("Input an interger m ")
 n = InputBox("Input an interger n")
 Call GCD(m, n)
 End Sub[/FONT]

[FONT=Courier New]Dim m As Integer
 Dim n As Integer
 Dim r As Integer   'location 4
 Sub GCD(m, n)
 Do
 r = m Mod n
 If r <> 0 Then
 m = n: n = r
 End If
 Loop While r <> 0
 MsgBox n & " is GCD"   'Correct ans.
 End Sub

 Private Sub CommandButton1_Click()
 m = InputBox("Input an interger m ")
 n = InputBox("Input an interger n")
 Call GCD(m, n)
 End Sub[/FONT]

 

[njimack]

If you make your variables Public, then you only need to declare them once. I usually list them all in a separate module...
Public m as Integer
Public n as Integer
etc
etc

 

[alee001]

If you make your variables Public, then you only need to declare them once. I usually list them all in a separate module...
Public m as Integer
Public n as Integer
etc
etc

Your mean Public suit for once variable and Private suit for many time variable?

 

[njimack]

No, for any variable used in more than one procedure, declare them as Public.