The Königsberg Bridge Problem is a historical puzzle asking if it's possible to walk through the city of Königsberg, crossing each of its seven bridges exactly once. Leonhard Euler proved it's impossible because there were more than two landmasses connected by an odd number of bridges, a key insight that laid the foundation for graph theory.
Someone who is addicted to obtaining money and building wealth. A money addict and fanatic. Breadheads often work more than one full-time job, and some even participate in illicit activities to "obtain the bread".