void relax(Edge e) {
	if (dist_to[e.getSourceVertex()] + e.weight < dist_to[e.getiDestinationVertex()]) {
		dist_to[e.getDestinationVertex()] = dist_to[e.getSourceVertex()] + e.weight;
		edge_to[e.getDestinationVertex()] = e.getSourceVertex();
	}
}


void bellmanFord(Graph g) {
	for (Vertex v : g) {
		for (Edge e : g) {
			relax(e);
		}
	}
}