Private Sub Worksheet_Change(ByVal Target As Range)
Dim a As Integer
For a = 1 To 50
     If Cells(a, 1).Value = 1 Then
         Rows(a).Hidden = True
         Else
         Rows(a).Hidden = False
     End If
Next a
End Sub

Private Sub Worksheet_Change(ByVal Target As Range)

Dim rng, out, out1, i, one, zero
Dim Col
Set rng = Range(Cells(1, 1), Cells(300, 1))
Col = rng
one = True
zero = True

With rng.Cells(1, 1)
     For Each v In Col
     i = i + 1
         If v = 1 Then
             If one Then
             Set out = .Offset(i - 1)
             one = False
             Else
             Set out = Union(out, .Offset(i - 1))
             End If
         End If
         If v = 0 Then
             If zero Then
             Set out1 = .Offset(i - 1)
             zero = False
             Else
             Set out1 = Union(out1, .Offset(i - 1))
             End If
         End If
     Next
End With

End Sub