🚀 go-pugleaf

In article <2qt8ce$mbk@news1.digex.net>
mikej@access2.digex.net (Mike Jacobs) writes:
 
>the hundreds digit:
>even, it's a loop and will eventually return (the beltway)
>odd, it's a spur and won't come back
>
>of course they don't aways work this way:  I270 & I370 are mutants...
>(i've seen on an old map that I270 used to be I70N/S while I70E/W
>continued to baltimore!)
>
>--
>Mike Jacobs            |  A new koan:
 
Slightly more generally:  the hundreds digit is even when the road connects
at both ends with other interstates (or doesn't have ends).  This covers
I-270.
 
The hundreds digit is odd when the road connects with an interstate at one
end but not the other.
 
There's a problem when a road was built to connect to another interstate
that hasn't been built yet (or may never be built).  I-295 runs from the
Washington Beltway into DC, but I'm not sure whether it ends at the SE
freeway (not an interstate) or continues to I-395 (to validate its number).
 
-Neal Plotkin          nplotkin@mitre.org
MITRE Corporation      (703) 883-7167
7525 Colshire Dr
McLean VA 22102