In practice I've used TreeSet as an alias of "ordered list with no repetitions". HashSet I've used to check what has been processed vs what still needs to be processed.
But often I just end up using a Map instead. They're often more useful.
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In practice I've used TreeSet as an alias of "ordered list with no repetitions". HashSet I've used to check what has been processed vs what still needs to be processed.
But often I just end up using a Map instead. They're often more useful.