Two examples of interesting TSP Applications I came across:
The people in charge of creating routes for school buses and bus routes in general use the Traveling Salesman problem to drop off their passengers in the most optimal way possible while bringing the bus back to the original location.
Some Airlines like Southwest use TSP to schedule flight paths so that their crews fly to several different locations and come back to their home airport at the end of their shifts. Other airlines have their planes just fly back and forth between airports which results in a much simpler solution to bring the crew back to their home airport, but also is a less optimized use of resources.
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