Câu c: Số chính phương

Private Function SCP(x As Integer) As Boolean
        Dim kq As Boolean
        Dim a As Integer
        a = Math.Sqrt(x)
        If a * a = x Then
            kq = True
        Else
            kq = False
        End If

        SCP = kq
    End Function
    Private Sub CmdIn_Click(sender As Object, e As EventArgs) Handles CmdIn.Click
        Dim n, i As Integer
        Dim ax As String
        ax = "Các số chính phương:   "
        Do While n <= 0
            n = InputBox("Nhap vao mot so nguyen duong: ", "Nhap", 0)
        Loop
        For i = 1 To n
            If SCP(i) = True Then
                ax = ax + "     " & i & vbCrLf
            End If
        Next
        TxtOut.Text = ax
    End Sub


    Private Sub TxtOut_TextChanged(sender As Object, e As EventArgs) Handles TxtOut.TextChanged
        TxtOut.ScrollBars = ScrollBars.Vertical
    End Sub