
Leonard Euler's Solution to the Konigsberg Bridge Problem (2006) - jpelecanos
https://www.maa.org/press/periodicals/convergence/leonard-eulers-solution-to-the-konigsberg-bridge-problem
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computator
When I first saw this problem in elementary school, I went to look at an atlas
to see if I could see the bridges (but couldn't because the scale in an atlas
was too large). I'm just blown away that today, not only can I find the map
but I can look at the aerial view and go on virtual walks through the city and
the bridges -- mere seconds after reading about it:

[https://www.google.ca/maps/place/Kaliningrad,+Kaliningrad+Ob...](https://www.google.ca/maps/place/Kaliningrad,+Kaliningrad+Oblast,+Russia/@54.7064027,20.502857,15z/)

I'm wondering what the amazing mapping advance will be 20 years from now. Real
time street views of all metropolitan areas?

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stevoski
I visited Kaliningrad in 2007 and puzzled my hosts by asking them if I could
see the famous bridges. They hadn't heard of Euler and the Bridges of
Königsberg. I was astonished.

We drove around and saw a couple of what I think were the bridges dating from
Euler's time. Others had been destroyed in WW2 and/or replaced with modern,
larger bridges.

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JadeNB
> Others had been destroyed in WW2 and/or replaced with modern, larger
> bridges.

I read a while ago that the destruction had actually rendered the bridges
problem soluble (that is, that there _is_ a modern Eulerian path); but I don't
know if that was true at the time, or is still true.

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OscarCunningham
From Google Maps it seem like it currently is possible to walk all the
bridges, although you can't end where you started. Two of the original bridges
have gone, two more have been built (not in the same locations as the
destroyed ones), and there are two additional bridges that are within the city
limits now but wouldn't have been in Euler's time.

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JadeNB
I love it: the nine _new_ bridges of Königsberg! (It would never have occurred
to me to check on Google Maps; thanks!)

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marchenko
Would traveling to the source of the river Pregel and walking around it count
as a solution?

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lainga
Alas! One of the Pregel's tributaries originates in a lake which is itself
linked by a canal to the Baltic, forming a loop excluding Konigsberg.

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lemoncucumber
Reading the post title, my first reaction was "Wow, Euler must have been
really stumped if it took him until 2006 to solve the problem."

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k__
I found it kinda funny that most lectures in my Math 101 started with "the
little Euler" or "the little Gauss". Like those guys did all of Math on their
own when they were children, haha.

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captain_perl
Well, Euler and Gauss knew all there was to know about mathematics at the
time. That consisted of algebra up to quintic equations plus their own
inventions.

You'd be unpleasantly surprised if you saw a turn-of-the century-math high
school textbook (1900 or so.) Pretty advanced stuff towards the end.

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p1esk
_That consisted of algebra up to quintic equations plus their own inventions_

Well, calculus had been invented before Euler was born, and a lot of advanced
math had been developed by the time Gauss appeared (a lot of it by none other
than Euler).

