The travelling salesman problem (TSP) asks the following question: “Given a list of cities and the distances between each pair of cities, what is the shortest possible route that visits each city exactly once and returns to the origin city?”
I think that a problem cannot be effective resolved until all the variables are calculated.
The Travelling Salesman problem of finding the shortest route between start and a number of destinations is that short is not really the optimal solution.
Given that 80% of business arises from 20% of customers, owing to volume or repeat custom, not all city destinations would necessarily be included in every trip and preference to higher volume destinations and greater speed at inventory turn over.
Also, if one is servicing business rather than direct to the public, that also is a factor.
While the math matter remains, the social practice of door to door sales is obsolete in the internet era.
Sears Roebuck Catalog the 1800 Amazon while ebay is the online second hand market.
The only door knockers continue to be Godbots of various types and that is needing to be dealt with civilly in law as trespassing and frankly, bordering on civil terrorism.
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