Excel VBA计算1！+2！+3！+...+n!

Option Explicit

Sub main_fact()
Dim n As Long
Dim i As Integer, b As Double, sum As Double
sum = 0
n = InputBox("请输入N")
For i = 1 To n
b = fact(i)
sum = sum + b
Next
MsgBox sum
End Sub


Public Function fact(ByVal i As Integer) As Double

Dim a As Integer, sum As Double
sum = 1
For a = 1 To i
sum = sum * a
Next a
fact = sum
End Function

Edited by 0001lzb,a WHUer