vb编程分别编写5个函数与过程：求和，求阶乘，求绝对值，求质数判断，求3个数的最大数

求和函数

function sum(x as integer,y as integer)as integer

sum=x+y

end function

求阶乘函数

Function jc(n as integer)

if n=1 then

jc=1

Else

jc=jc(N-1)*n

end if

End Function

求绝对值

function jdz(x as integer)

jdz=abs(x)

end function

判断质数

sub zs()

Dim a As Integer

Dim b As Integer

Dim number As String

number = InputBox("输入数字")

a = number

Dim Flag As Boolean

Flag = True

For b = 2 To Sqr(a) '不用判断到a-1,只要到 Sqr(A)就OK了

If a Mod b = 0 Then

Flag = False

Exit For

End If

Next

If Flag = True Then

Print "是质数"

Else

Print "不是质数"

End If end sub