//(@
//import java.lang.*;
//@)
Container = "(" <contents> List(Item) <capacity> Capacity ")".
Item : Container | Simple. 
List(S) ~ {S}.
Simple = <name> ItemName <w> Weight .
ItemName = <i> Ident.
Capacity = <i> Integer.
Weight = <i> Integer.


SummingVisitor = <total> Integer.
CountingVisitor = <total> Integer.
AverageVisitor = 
<cV> CountingVisitor
<sV> SummingVisitor
<current> Float.

Main = .