(was: How are these "minimal paths" called?) Since only a few knew what I'm talking about, I'll reformulate the problem and hope for a better understanding.
Let V be be set of cities, E (containing some two-element sets of elements of V) is the set of connections between some cities, all these connectons have cost 1. Other connections (i.e. not in E) cost infinity. (I.e. the salesman goes only through the connections listed in E). Let W be a subset of V. Questions: (1) Find a shortest path which goes at least once through each city in W (and is allowed to visit cities in V\W)? (2) What is the cost of such shortest path?
-- Best regards, Alex.
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