WClique problem
WDominating set
WEdge dominating set
WFeedback arc set
WGood spanning tree
WGraph coloring
WHamiltonian path
WIndependent set (graph theory)
WInstant Insanity
WMaximal independent set
WMaximum cut
WMaximum flow problem
WNonblocker
WOdd cycle transversal
WRadio coloring
WShortest path problem
WSnake-in-the-box
WSpanning tree
WSteiner tree problem
WTravelling salesman problem
WVertex cover
WWidest path problem