```
Sub ZeroButton()
Dim r As Long
' Find next row to populate
r = Cells(Rows.Count, "A").End(xlUp).Row + 1
' Verify row selection
If r < 7 Then
r = 7
Else
If r > 47 Then
MsgBox "Cell A47 already populated", vbOKOnly
Exit Sub
End If
End If
' Populate cell
Cells(r, "A") = 0
End Sub
Sub OneButton()
Dim r As Long
' Find next row to populate
r = Cells(Rows.Count, "A").End(xlUp).Row + 1
' Verify row selection
If r < 7 Then
r = 7
Else
If r > 47 Then
MsgBox "Cell A47 already populated", vbOKOnly
Exit Sub
End If
End If
' Populate cell
Cells(r, "A") = 1
End Sub
```