下面这个Sub过程的功能是统计字符串中“a”的个数，请在空白处填上合适的代码完成程序。 Private Sub numCount() Dim hum As Integer s＄ = "software And hardware" num = Len(s$) For i = 1 To hum b$=______ If b$ = "a" Then x = x+1 Next i Print "x="; x End Sub

下列这个Sub过程的功能是：统计字符串中“a”的个数，请在空白处填上合适的代码，将程序补充完整。 Private Sub numCount() Dim num As Integer S$="software And hardware" num=Len(s$) For i=1 To num b$=______ Ifb$="a" Then x=x+1 Next i Print "x=";x End Sub