Imports System.Math
Public Class Form1

    Function mvod(ByVal T As TextBox)
        Return Val(T.Text)
    End Function

    Overloads Sub mvivod(ByVal r As Double, ByVal T As TextBox)
        T.Text = CStr(r)
    End Sub

    Overloads Sub mvivod(ByVal n As Integer, ByVal T As TextBox)
        T.Text = CStr(n)
    End Sub


    Sub cool(ByVal x As Double, ByVal y As Double, ByVal z As Double, ByVal c As Double, ByRef r As Double, ByRef n As Integer)
        Dim cy, kx, tx, z3 As Double
        cy = c * y
        kx = x ^ (1 / 2)
        tx = Tan(x)
        z3 = z ^ 3
        If cy > kx Then
            r = cy
        Else
            r = kx
        End If
        If y * z > 0 And x > 0 Then

            If (r > y) Then
                r = y
            End If

            If (r > z) Then
                r = z
            End If
            n = 1

        Else
            If y * z < 0 And x > 0 Then
                If (tx > z3) Then
                    r = z3
                Else
                    r = tx
                End If
                n = 2
            Else
                n = 3
                r = 15
            End If
        End If
    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim x, y, z, c, r As Double, n As Integer
        x = mvod(TextBox1)
        y = mvod(TextBox2)
        z = mvod(TextBox3)
        c = mvod(TextBox4)
        cool(x, y, z, c, r, n)
        mvivod(r, TextBox5)
        mvivod(n, TextBox6)

    End Sub
End Class