@Test
 public void testAlreadySolved() {
   CobwebSolver solver = new CobwebSolver(new CobwebGraph(3).map);
   solver.setEdge(1, 2, Edge.EdgeOperation.DIVISION, 2);
   solver.setEdge(3, 2, Edge.EdgeOperation.ADDITION, 1);
   solver.setEdge(1, 3, Edge.EdgeOperation.DIVISION, 3);
   solver.setNode(1, 6);
   solver.setNode(2, 3);
   solver.setNode(3, 2);
   assertEquals(CobwebSolver.SolverState.SOLVED_ALREADY, solver.numberOfSolutions());
 }
  @Test
  public void testSolverInit() {
    CobwebGraph cw = new CobwebGraph(3);
    CobwebSolver solver = new CobwebSolver(cw.map);
    assertTrue(solver.hasUnreachableNodes());
    solver.setEdge(1, 2, Edge.EdgeOperation.ADDITION, 1);
    solver.setEdge(1, 3, Edge.EdgeOperation.ADDITION, 1);
    assertFalse(solver.hasUnreachableNodes());

    assertEquals(null, solver.getNodeValue(1));
    solver.setNode(1, 5);
    assertTrue(solver.getNodeValue(1).equals(5));
  }