// open input
            BufferedReader in = new BufferedReader(new FileReader(args[0]));
            
            // get # of vertices & edges
            String [] init = in.readLine().split("[ \t\n\r\f]");            
            vertex_total = Integer.parseInt(init[0]);
            edge_total = Integer.parseInt(init[2]);

            // initialize adjacency matrix
            vertices = new boolean[vertex_total];
            edges = new ArrayList <LinkedList <Integer>>(vertex_total);    

            // initialize all elements of arraylist
            for (int i = 0; i < vertex_total; i++){
                edges.add(i, new LinkedList <Integer>());
            }
    
            // create adjacency matrix for depth first search
            in.readLine();
            for (int i = 0; i < edge_total; i++){
                if (i% 10000 == 0){
                System.out.println(i);
                }            
                String [] line = in.readLine().split("[ \t\n\r\f]");
                int v = Integer.parseInt(line[0]);
                int e = Integer.parseInt(line[2]);
                                        
                edges.get(v).addFirst(e);
                edges.get(e).addFirst(v);
            }