Update Dijkstra's to use incidences instead of neighbors, and with it custom edge weights

src/algorithms.rs

@@ -92,19 +92,17 @@ where
     });
 
     while let Some(v) = heap.pop() {
-        for adjacent in graph.adjacent_vertices(v.vertex) {
-            // TODO: Use custom edge weights in Dijkstra's algorithm.
-            let edge_weight = 1;
-            let new_distance = distances[v.vertex].unwrap() + edge_weight;
-            if match distances[adjacent] {
+        for incidence in graph.incidences(v.vertex) {
+            let new_distance = distances[v.vertex].unwrap() + weight(incidence.1);
+            if match distances[incidence.0] {
                 None => true,
                 Some(old_distance) if old_distance > new_distance => true,
                 _ => false,
             } {
-                distances[adjacent] = Some(new_distance);
-                on_relax(adjacent, v.vertex);
+                distances[incidence.0] = Some(new_distance);
+                on_relax(incidence.0, v.vertex);
                 heap.push(DistanceOrderedVertex {
-                    vertex: adjacent,
+                    vertex: incidence.0,
                     distance: new_distance,
                 });
             }