Once you're a Jet, you're a Jet all the way. Unless you get traded to another team.

Or if they tear down your section of the Upper West Side right after your movie is filmed to make way for a cultural institution.

Actually, this could be a great place to go off on tangents about the graph, the movie, the city, . . .

For example, I debated whether the endpoints of the compound inequality should be open or closed. Are you still a Jet if you're dead? Not according to the song, which is, in point of fact, a little too sad to believe that you're forgotten that easily. I mean, (SPOILER ALERT) Tony's dead and they carried him off together, but did they forget all about him a day later? I don't know the answer to this. However, it occurred to me that you'd still be a Jet on that day that you died, up to the point of death. Ergo, closed circle.

So "1st cigarette < Jet < last dying day".

Translating this into Set-Builder Notation is left as an exercise to the reader.
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