The traveling salesman problem is a problem in graph theory requiring the most efficient (i.e., least total distance) Hamiltonian
cycle a salesman can take through each of cities. No general method of solution is known, and the problem
is NP-hard.

The traveling salesman problem is mentioned by the character Larry Fleinhardt in the Season 2 episode "Rampage"
(2006) of the television crime drama NUMB3RS.

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