Print an Adjacency List Graph

// print the graph
void printGraph(Graph G) {
	for (int j = 1; j <= G->numV; j++) {
		printf("%s: ", G->vertex[j].id);
		GEdgePtr p = G->vertex[j].firstEdge;
		while (p != NULL) {
			printf("%s %d ", G->vertex[p->child].id, p->weight);
			p = p->nextEdge;
		}
		printf("\n");
	}
}