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Mathematics

The Traveling Salesman Problem and Approximation Algorithms

Quick fact

The number of possible routes for just 20 cities is about 1.2 quintillion – that's more than the number of grains of sand on Earth.

Why this is interesting

Imagine you're a salesperson who must visit multiple cities and return home. What's the shortest route? For a handful of cities it's easy, but add just a few more and solving it perfectly might take longer than the age of the universe.