code: private Map<Integer, Set<Integer>> getGLBCCPotentialNeighbors(int cc) {
  		Map<Integer, Set<Integer>> ccPotentialNeighbors = new HashMap<>();
  		// Retrieve all nodes of CC
  		Set<Integer> ccNodes = getGLBCCNodes(cc);
  		// Retrieve neighbors of the nodes of CC that are outside the CC
  		for (int i : ccNodes) {
  			Set<Integer> outNeighbors = new HashSet<>();
  			for (int j : g.getPotNeighOf(i)) {
  				if (!ccNodes.contains(j)) {
  					outNeighbors.add(j);
  				}
  			}
  			if (outNeighbors.size() > 0) {
  				ccPotentialNeighbors.put(i, outNeighbors);
  			}
  		}
  		return ccPotentialNeighbors;
  	}
docs: Retrieve the potential CC neighbors (i.e. not in the CC) of a GLB CC.
  
  @param cc The GLB CC index.
  @return A map with frontier nodes of the CC as keys (Integer), and their potential neighbors that are
  outside the CC (Set<Integer>). Only the frontier nodes that have at least one potential neighbor outside the
  CC are stored in the map.
  {
  frontierNode1: {out-CC potential neighbors},
  frontierNode3: {...},
  ...
  }