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   Hamiltonian completion
   The Hamiltonian completion problem is to find the minimal number of edges to add to a graph to make it Hamiltonian. The problem is clearly NP-hard in general case (since its solution gives an answer to the NP-complete problem of determining whether a given graph has a Hamiltonian cycle). The associ...
   Found op http://en.wikipedia.org/wiki/Hamiltonian_completion
   
   

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