Or the following input: 

aa|s1
bb|s1
bb|s2
cc|s2
cc|s3
aa|s3
cc|s4
dd|s4
aa|s4

[download]
Yields a ["s4"]. How to interpret that result?

In reply to Re^2: Contemplating some set comparison tasks by oiskuu
in thread Contemplating some set comparison tasks by dwhite20899

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