堆栈空间溢出解决方案

堆栈空间溢出
VB code
Dim Pi!
Private Function s(n As Long) As Double
If n = 1 Then
s = 1
Else
  If n Mod 2 = 0 Then
  s = (-1) / (2 * n - 1) + s(n - 1)
  Else
  s = 1 / (2 * n - 1) + s(n - 1)
  End If
End If
End Function
Private Sub Form_click()
Pi = s(5074)
Pi = 4 * Pi
Print Pi
End Sub


n最大只能取到5704,取5705就溢出了.。。。
当n的值过大时,程序提示堆栈空间溢出,请问怎么修改???


------解决方案--------------------
VB的栈空间只有1M,大的递归时,栈溢出是经常不可避免的,换一种算法,消除递归,再说,递归是低效的
------解决方案--------------------
Private Function s(n As Long) As Double
dim i as long, p as double
p = 1
for i = 2 to n
p = p * i
next
s = p
end function
------解决方案--------------------
没事别乱用递归。人不能迂腐。
------解决方案--------------------
可以用循环代替递归.