Imports System.Math
Public Class Form1

    Function mvvod(ByVal t As TextBox)
        Return Val(t.Text)
    End Function

    Sub mvivod(ByVal x As Double, ByVal t As TextBox)
        t.Text = CStr(x)
    End Sub

    Sub mvivodint(ByVal x As Integer, ByVal t As TextBox)
        t.Text = CStr(x)
    End Sub

    Sub novojenova(ByVal x As Double, ByVal z As Double, ByRef y As Double, ByRef n As Integer)

        If (x < 0 And z < 0) Then
            y = x
            If (y > z) Then
                y = z
            End If
            n = 1
        ElseIf (z > 0 And x > 0) Then
            y = x
            If (y < (x + z) ^ (1 / 3)) Then
                y = (x + z) ^ (1 / 3)
            End If
            If (y < Cos(x * z)) Then
                y = Cos(x * z)
            End If
            n = 2
        Else
            y = x + z
            n = 3
        End If
    End Sub




    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim x, z, y As Double, n As Double

        x = mvvod(TextBox1)
        z = mvvod(TextBox2)

        novojenova(x, z, y, n)
        mvivod(y, TextBox3)
        mvivodint(n, TextBox4)
    End Sub
End Class