Private Sub Form_Load()

ii = FreeFile
Open "D:\contoh.txt" For Output As #ii

Dim i, j, k, m, f1, f2, p, p1, p10, p100, p1000 As Integer
For i = 2 To 9
For j = 2 To 9
For k = 2 To 9
For m = 2 To 9
If i <> j And j <> k And k <> i And m <> i And m <> j And m <> k Then
        f1 = 10 * i + j
        f2 = 10 * k + m
        p = f1 * f2
    If p < 10000 Then
        p1 = p Mod 10
        p10 = (p Mod 100 - p1) / 10
        p100 = (p Mod 1000 - 10 * p10 - p1) / 100
        p1000 = (p - 100 * p100 - 10 * p10 - p1) / 1000
        If p1 > 1 And p10 > 1 And p100 > 1 And p1000 > 1 And p1 < 10 And p10 < 10 And p100 < 10 And p1000 < 10 And p1 <> i And p1 <> j And p1 <> k And p1 <> p10 And p10 <> i And p10 <> j And p10 <> k And p100 <> i And p100 <> j And p100 <> k And p100 <> p10 And p100 <> p1 And m <> p1 And m <> p10 And m <> p100 And p1000 <> i And p1000 <> j And p1000 <> k And p1000 <> m And p1000 <> p100 And p1000 <> p10 And p1000 <> p1 Then
            ' MsgBox (f1)
           ' MsgBox (f2)
           ' MsgBox (p)
            Print #ii, f1, "x", f2, "=", p
        End If
    End If
End If
Next m
Next k
Next j
Next i

Close #ii

End Sub