examples
........\graph
........\.....\clique.lp
........\.....\degree-bounded_connected_subgraph.lp
........\.....\graph1
........\.....\graph_isomorphism.lp
........\.....\hamiltonian_cycle.lp
........\.....\induced_path.lp
........\.....\k-closure.lp
........\.....\k-colorability.lp
........\.....\lizi.lp~
........\.....\longest_cycle.lp
........\.....\traveling_salesman.lp
........\.....\vertex_cover.lp
........\logic
........\.....\maxsat.lp
........\.....\sat.lp
........\planning
........\........\logistics.lp
........\........\plan1.lp
........\........\plan2.lp
........\puzzle
........\......\puzzle.lp
........\......\puzzle1.lp
........\......\puzzle3.lp