Найти периметр десятиугольника c заданными координатами вершин - VB

Private Sub Command1_Click()
Dim n As Long
n = 10 'inputbox("Введите к-во точек")
ReDim x(0 To n - 1) As Double, y(0 To n - 1) As Double
Dim i As Long
randomize
For i = 0 To n - 1
  x(i) = Rnd * n 'inputbox("X(" & i+1 & ")=")
  y(i) = Rnd * n 'inputbox("Y(" & i+1 & ")=")
Next i
Dim l As Double
For i = 1 To n
  l = l + Get_L(x(i - 1), y(i - 1), x(i Mod n), y(i Mod n))
Next i
MsgBox "L = " & l
End Sub
 
'процедура вычисления расстояния между двумя точками, заданными своими координатами
Function Get_L(x1 As Double, y1 As Double, x2 As Double, y2 As Double) As Double
Get_L = Sqr((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2))
End Function