CirculatQueue -- null string
Stem -- Null string
OrderedCollection -- The OrderedCollection class
This is working correctly. The stem class overrides the string method and returns the string value of the stem name (or the current assigned default value), since you did not supply a name when you created the instance, the value is the null string.
The OrderedCollection problem is a bug in your program. Since you did not create a new instance of the class, the correct string value of the class object is "The OrderedCollection class"
The CircularQueue class overrides the string method to return the items as a comma separated list. Since the queue is empty, just a null string is returned.
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