下面程序的功能是:读入 n 后,求算式 1+1/2 ! +1/3 ! +......+1/n !的值。所缺部分( )。 Private Sub Form_Click() dim sum as single, item as single dim nn as string dim i as integer, j as integer, n as integer nn = inputbox(" 请输入求的项数 n") n = val ( nn ) sum = 1 for i = 2 to n item = 1 for j = 1 to i item =______ next j sum = sum+1/item next i print "sum="; sum end sub