public int [] compute_outdegree() {
private int [] compute_outdegree() {
	public int [] compute_outdegree() {		int [] outdeg = new int[_graph.numVertices()];		for(int i = 0; i < _graph.numVertices(); i++) {			outdeg[i] = _vtx_index_tbl[i].outEdges().size();		}		return outdeg;	}