VB编程:已知下式成立：e=1+1/1!+1/2!+......+1/N! ...,计算e的值（精确到10的-6次方）

Private Sub Command1_Click()
Dim e As Double, s As Double, i%, j%, n%
n = Val(InputBox("请输入整数N吧!!"))
e = 1
For i = 1 To n
s = 1
For j = 1 To i
s = s * j
Next
e = e + 1 / s
Next
Print Format(e, "0.000001")
End Sub

Private Sub Command1_Click()
Dim e As Double, s As Double, i%, n%
n = Val(InputBox("请输入整数N吧!!"))
e = 1
For i = 1 To n
s = s * i
e = e + 1 / s
Next
Print Format(e, "0.000001")
End Sub

vb妮可 的算法作了点优化。
N！不需要每步如此计算，
可以使用：N! = (N-1)!*N。