# Does the graph of Konigsberg have an Euler path?

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## Does the graph of Königsberg have an Euler path?

In modern language, Euler shows that the possibility of a walk through a graph, traversing each edge exactly once, depends on the degrees of the nodes. Since the graph corresponding to historical Königsberg has four nodes of odd degree, it cannot have an Eulerian path.

## Does Königsberg exist?

The town of Königsberg straddles the Pregel River. It was formerly in Prussia, but is now known as Kaliningrad and is in Russia.

## Why is the Konigsberg bridge problem so famous?

Königsberg bridge problem, a recreational mathematical puzzle, set in the old Prussian city of Königsberg (now Kaliningrad, Russia), that led to the development of the branches of mathematics known as topology and graph theory. In demonstrating that the answer is no, he laid the foundation for graph theory.

## How was the Konigsberg problem solved?

In 1875, the people of Königsberg decided to build a new bridge, between nodes B and C, increasing the number of links of these two landmasses to four. This meant that only two landmasses had an odd number of links, which gave a rather straightforward solution to the problem.

## Is Prussia gone?

It was de facto dissolved by an emergency decree transferring powers of the Prussian government to German Chancellor Franz von Papen in 1932 and de jure by an Allied decree in 1947. The Kingdom of Prussia was thus abolished in favour of a republic—the Free State of Prussia, a state of Germany from 1918 until 1933.

## What is the bridge Riddle?

Can you figure out a way to have everyone escape in time? Remember: no more than two people can cross the bridge together, anyone crossing must either hold the lantern or stay right next to it, and any of you can safely wait in the dark on either side of the gorge.

## Which bridge have steps?

Known as a “clapper bridge,” which is a type of span built out of flat stone slabs lain end-to-end and supported by stone stacks, the Tarr Steps are maybe the best known example of this type of construction.