Leonhard Euler (1707 - 1783), a Swiss mathematician,
was one of the greatest and most prolific mathematicians of all time. Euler
spent much of his working life at the BerlinAcademy in Germany, and it was during that
time that he was given the "The Seven Bridges of Königsberg" question
to solve that has become famous.
The city of Königsberg straddles
the PregelRiver. It was formerly in Prussia,
but is now known as Kaliningrad and is in Russia.
Königsberg was situated close to the mouth of the river and had seven bridges
joining the two sides of the river and also an island and a peninsula.
So then; how do you get into Königsberg from Tula without crossing any