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- The town of Concentrië 1 answer
A version of the Travelling Salesman Problem, but with certain points.
We are talking about a town where 8 canals run from the middle boathouse into the city. You can only travel one way on the green canals.
The blue canals lie around the city in a circular shape. On the blue canals, you can travel both ways. You cannot turn half-way the canals, you may turn at a crossing of the canals. All the pieces of green canal have a length of 4, each piece of canal from canal to canal has a length of 3 (inner canal), 6 (middle canal) and 9 (outer canal).
You start at the central boathouse, from there, you need to deliver 6 packages to the red triangles. then, you have to go back to the central boathouse.
What is the shortest length of the route you can take to deliver those 6 packages?