diff --git a/api/kotlin-graphs.api b/api/kotlin-graphs.api
index c8504c3..4441d40 100644
--- a/api/kotlin-graphs.api
+++ b/api/kotlin-graphs.api
@@ -21,28 +21,31 @@ public final class io/github/alexandrepiveteau/graphs/ArcKt {
 	public static final fun arcTo-cK2_UGU (II)J
 }
 
-public abstract interface class io/github/alexandrepiveteau/graphs/DirectedGraph : io/github/alexandrepiveteau/graphs/Graph {
-	public static final field Companion Lio/github/alexandrepiveteau/graphs/DirectedGraph$Companion;
+public abstract interface class io/github/alexandrepiveteau/graphs/Directed {
 	public abstract fun contains--OaZVeM (J)Z
 }
 
+public abstract interface class io/github/alexandrepiveteau/graphs/DirectedGraph : io/github/alexandrepiveteau/graphs/Directed, io/github/alexandrepiveteau/graphs/Graph {
+	public static final field Companion Lio/github/alexandrepiveteau/graphs/DirectedGraph$Companion;
+}
+
 public final class io/github/alexandrepiveteau/graphs/DirectedGraph$Companion {
 }
 
 public final class io/github/alexandrepiveteau/graphs/DirectedGraph$DefaultImpls {
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/DirectedGraph;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/DirectedGraph;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/DirectedGraph;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/DirectedGraph;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/DirectedGraph;I)I
 }
 
 public final class io/github/alexandrepiveteau/graphs/DirectedGraphKt {
-	public static final fun toUndirectedGraph (Lio/github/alexandrepiveteau/graphs/DirectedGraph;)Lio/github/alexandrepiveteau/graphs/UndirectedGraph;
-	public static final fun transposed (Lio/github/alexandrepiveteau/graphs/DirectedGraph;)Lio/github/alexandrepiveteau/graphs/DirectedGraph;
+	public static final fun toUndirectedGraph (Lio/github/alexandrepiveteau/graphs/Directed;)Lio/github/alexandrepiveteau/graphs/UndirectedGraph;
+	public static final fun transposed (Lio/github/alexandrepiveteau/graphs/Directed;)Lio/github/alexandrepiveteau/graphs/DirectedGraph;
 }
 
 public abstract interface class io/github/alexandrepiveteau/graphs/DirectedNetwork : io/github/alexandrepiveteau/graphs/DirectedGraph, io/github/alexandrepiveteau/graphs/Network {
 	public static final field Companion Lio/github/alexandrepiveteau/graphs/DirectedNetwork$Companion;
-	public abstract fun weight--OaZVeM (J)I
 }
 
 public final class io/github/alexandrepiveteau/graphs/DirectedNetwork$Companion {
@@ -50,11 +53,15 @@ public final class io/github/alexandrepiveteau/graphs/DirectedNetwork$Companion
 
 public final class io/github/alexandrepiveteau/graphs/DirectedNetwork$DefaultImpls {
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;II)I
+	public static fun successorWeight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;II)I
+	public static fun successorWeight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;I)I
-	public static fun weight--OaZVeM (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;J)I
-	public static fun weight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;II)I
-	public static fun weight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;II)I
+}
+
+public final class io/github/alexandrepiveteau/graphs/DirectedNetworkKt {
+	public static final fun successorWeight-hOs2cps (Lio/github/alexandrepiveteau/graphs/Directed;J)I
 }
 
 public final class io/github/alexandrepiveteau/graphs/Edge {
@@ -79,20 +86,13 @@ public final class io/github/alexandrepiveteau/graphs/EdgeKt {
 	public static final fun edgeTo-cK2_UGU (II)J
 }
 
-public abstract interface class io/github/alexandrepiveteau/graphs/Graph {
-	public abstract fun contains-dT2TSiQ (I)Z
-	public abstract fun getSize ()I
-	public abstract fun index-dT2TSiQ (I)I
-	public abstract fun successor-_QOBl-4 (II)I
-	public abstract fun successor-vAesux8 (II)I
-	public abstract fun successorsSize (I)I
-	public abstract fun successorsSize-dT2TSiQ (I)I
-	public abstract fun vertex-1Pv3iCI (I)I
+public abstract interface class io/github/alexandrepiveteau/graphs/Graph : io/github/alexandrepiveteau/graphs/Successors, io/github/alexandrepiveteau/graphs/VertexSet {
 }
 
 public final class io/github/alexandrepiveteau/graphs/Graph$DefaultImpls {
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/Graph;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/Graph;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/Graph;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/Graph;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/Graph;I)I
 }
 
@@ -102,7 +102,8 @@ public abstract interface class io/github/alexandrepiveteau/graphs/MutableDirect
 public final class io/github/alexandrepiveteau/graphs/MutableDirectedGraph$DefaultImpls {
 	public static fun addVertices (Lio/github/alexandrepiveteau/graphs/MutableDirectedGraph;)Lio/github/alexandrepiveteau/graphs/Vertices;
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableDirectedGraph;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableDirectedGraph;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableDirectedGraph;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableDirectedGraph;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableDirectedGraph;I)I
 }
 
@@ -121,11 +122,11 @@ public final class io/github/alexandrepiveteau/graphs/MutableDirectedNetwork$Def
 	public static fun addArc--OaZVeM (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;J)V
 	public static fun addVertices (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;)Lio/github/alexandrepiveteau/graphs/Vertices;
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;II)I
+	public static fun successorWeight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;II)I
+	public static fun successorWeight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;I)I
-	public static fun weight--OaZVeM (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;J)I
-	public static fun weight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;II)I
-	public static fun weight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableDirectedNetwork;II)I
 }
 
 public abstract interface class io/github/alexandrepiveteau/graphs/MutableDirectedNetworkScope : io/github/alexandrepiveteau/graphs/MutableDirectedGraphScope, io/github/alexandrepiveteau/graphs/MutableNetworkScope {
@@ -145,7 +146,8 @@ public abstract interface class io/github/alexandrepiveteau/graphs/MutableGraph
 public final class io/github/alexandrepiveteau/graphs/MutableGraph$DefaultImpls {
 	public static fun addVertices (Lio/github/alexandrepiveteau/graphs/MutableGraph;)Lio/github/alexandrepiveteau/graphs/Vertices;
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableGraph;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableGraph;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableGraph;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableGraph;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableGraph;I)I
 }
 
@@ -164,10 +166,11 @@ public abstract interface class io/github/alexandrepiveteau/graphs/MutableNetwor
 public final class io/github/alexandrepiveteau/graphs/MutableNetwork$DefaultImpls {
 	public static fun addVertices (Lio/github/alexandrepiveteau/graphs/MutableNetwork;)Lio/github/alexandrepiveteau/graphs/Vertices;
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableNetwork;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableNetwork;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableNetwork;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableNetwork;II)I
+	public static fun successorWeight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/MutableNetwork;II)I
+	public static fun successorWeight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableNetwork;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableNetwork;I)I
-	public static fun weight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/MutableNetwork;II)I
-	public static fun weight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableNetwork;II)I
 }
 
 public abstract interface class io/github/alexandrepiveteau/graphs/MutableNetworkScope : io/github/alexandrepiveteau/graphs/MutableGraphScope {
@@ -183,7 +186,8 @@ public abstract interface class io/github/alexandrepiveteau/graphs/MutableUndire
 public final class io/github/alexandrepiveteau/graphs/MutableUndirectedGraph$DefaultImpls {
 	public static fun addVertices (Lio/github/alexandrepiveteau/graphs/MutableUndirectedGraph;)Lio/github/alexandrepiveteau/graphs/Vertices;
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableUndirectedGraph;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableUndirectedGraph;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableUndirectedGraph;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableUndirectedGraph;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableUndirectedGraph;I)I
 }
 
@@ -202,10 +206,11 @@ public final class io/github/alexandrepiveteau/graphs/MutableUndirectedNetwork$D
 	public static fun addEdge-zEWoN30 (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;J)V
 	public static fun addVertices (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;)Lio/github/alexandrepiveteau/graphs/Vertices;
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;II)I
+	public static fun successorWeight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;II)I
+	public static fun successorWeight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;I)I
-	public static fun weight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;II)I
-	public static fun weight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;II)I
 	public static fun weight-zEWoN30 (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetwork;J)I
 }
 
@@ -220,19 +225,16 @@ public final class io/github/alexandrepiveteau/graphs/MutableUndirectedNetworkSc
 	public static fun addVertices (Lio/github/alexandrepiveteau/graphs/MutableUndirectedNetworkScope;)Lio/github/alexandrepiveteau/graphs/Vertices;
 }
 
-public abstract interface class io/github/alexandrepiveteau/graphs/Network : io/github/alexandrepiveteau/graphs/Graph {
-	public abstract fun weight (II)I
-	public abstract fun weight-9scIZJg (II)I
-	public abstract fun weight-cK2_UGU (II)I
-	public abstract fun weight-iNgu2Tg (II)I
+public abstract interface class io/github/alexandrepiveteau/graphs/Network : io/github/alexandrepiveteau/graphs/Graph, io/github/alexandrepiveteau/graphs/SuccessorsWeight {
 }
 
 public final class io/github/alexandrepiveteau/graphs/Network$DefaultImpls {
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/Network;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/Network;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/Network;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/Network;II)I
+	public static fun successorWeight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/Network;II)I
+	public static fun successorWeight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/Network;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/Network;I)I
-	public static fun weight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/Network;II)I
-	public static fun weight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/Network;II)I
 }
 
 public final class io/github/alexandrepiveteau/graphs/NoSuchArcException : java/util/NoSuchElementException {
@@ -247,17 +249,66 @@ public final class io/github/alexandrepiveteau/graphs/NoSuchVertexException : ja
 	public fun <init> ()V
 }
 
-public abstract interface class io/github/alexandrepiveteau/graphs/UndirectedGraph : io/github/alexandrepiveteau/graphs/Graph {
-	public static final field Companion Lio/github/alexandrepiveteau/graphs/UndirectedGraph$Companion;
+public abstract interface class io/github/alexandrepiveteau/graphs/Predecessors : io/github/alexandrepiveteau/graphs/VertexSet {
+	public abstract fun predecessor-_QOBl-4 (II)I
+	public abstract fun predecessor-vAesux8 (II)I
+	public abstract fun predecessorsSize (I)I
+	public abstract fun predecessorsSize-dT2TSiQ (I)I
+}
+
+public final class io/github/alexandrepiveteau/graphs/Predecessors$DefaultImpls {
+	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/Predecessors;I)Z
+	public static fun predecessor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/Predecessors;II)I
+	public static fun predecessorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/Predecessors;I)I
+}
+
+public abstract interface class io/github/alexandrepiveteau/graphs/Successors : io/github/alexandrepiveteau/graphs/VertexSet {
+	public abstract fun successorIndex (II)I
+	public abstract fun successorIndex-iNgu2Tg (II)I
+	public abstract fun successorVertex-_QOBl-4 (II)I
+	public abstract fun successorVertex-vAesux8 (II)I
+	public abstract fun successorsSize (I)I
+	public abstract fun successorsSize-dT2TSiQ (I)I
+}
+
+public final class io/github/alexandrepiveteau/graphs/Successors$DefaultImpls {
+	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/Successors;I)Z
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/Successors;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/Successors;II)I
+	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/Successors;I)I
+}
+
+public abstract interface class io/github/alexandrepiveteau/graphs/SuccessorsWeight : io/github/alexandrepiveteau/graphs/Successors {
+	public abstract fun successorWeight (II)I
+	public abstract fun successorWeight-9scIZJg (II)I
+	public abstract fun successorWeight-cK2_UGU (II)I
+	public abstract fun successorWeight-iNgu2Tg (II)I
+}
+
+public final class io/github/alexandrepiveteau/graphs/SuccessorsWeight$DefaultImpls {
+	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;I)Z
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;II)I
+	public static fun successorWeight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;II)I
+	public static fun successorWeight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;II)I
+	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;I)I
+}
+
+public abstract interface class io/github/alexandrepiveteau/graphs/Undirected {
 	public abstract fun contains-zEWoN30 (J)Z
 }
 
+public abstract interface class io/github/alexandrepiveteau/graphs/UndirectedGraph : io/github/alexandrepiveteau/graphs/Graph, io/github/alexandrepiveteau/graphs/Undirected {
+	public static final field Companion Lio/github/alexandrepiveteau/graphs/UndirectedGraph$Companion;
+}
+
 public final class io/github/alexandrepiveteau/graphs/UndirectedGraph$Companion {
 }
 
 public final class io/github/alexandrepiveteau/graphs/UndirectedGraph$DefaultImpls {
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/UndirectedGraph;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/UndirectedGraph;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/UndirectedGraph;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/UndirectedGraph;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/UndirectedGraph;I)I
 }
 
@@ -282,10 +333,11 @@ public final class io/github/alexandrepiveteau/graphs/UndirectedNetwork$Companio
 
 public final class io/github/alexandrepiveteau/graphs/UndirectedNetwork$DefaultImpls {
 	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;I)Z
-	public static fun successor-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;II)I
+	public static fun successorIndex-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;II)I
+	public static fun successorVertex-_QOBl-4 (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;II)I
+	public static fun successorWeight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;II)I
+	public static fun successorWeight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;II)I
 	public static fun successorsSize-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;I)I
-	public static fun weight-cK2_UGU (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;II)I
-	public static fun weight-iNgu2Tg (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;II)I
 	public static fun weight-zEWoN30 (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;J)I
 }
 
@@ -372,6 +424,17 @@ public final class io/github/alexandrepiveteau/graphs/VertexMapKt {
 	public static final fun forEach-TXWKjJg ([ILkotlin/jvm/functions/Function2;)V
 }
 
+public abstract interface class io/github/alexandrepiveteau/graphs/VertexSet {
+	public abstract fun contains-dT2TSiQ (I)Z
+	public abstract fun getSize ()I
+	public abstract fun index-dT2TSiQ (I)I
+	public abstract fun vertex-1Pv3iCI (I)I
+}
+
+public final class io/github/alexandrepiveteau/graphs/VertexSet$DefaultImpls {
+	public static fun contains-dT2TSiQ (Lio/github/alexandrepiveteau/graphs/VertexSet;I)Z
+}
+
 public abstract interface class io/github/alexandrepiveteau/graphs/Vertices {
 	public abstract fun component1-IrpSQec ()I
 	public abstract fun component2-IrpSQec ()I
@@ -398,33 +461,40 @@ public final class io/github/alexandrepiveteau/graphs/Vertices$DefaultImpls {
 }
 
 public final class io/github/alexandrepiveteau/graphs/algorithms/Algorithms {
-	public static final fun connectedComponents (Lio/github/alexandrepiveteau/graphs/UndirectedGraph;)Lkotlin/Pair;
-	public static final fun maxFlowEdmondsKarp-SPb1_vQ (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;II)Lio/github/alexandrepiveteau/graphs/DirectedNetwork;
-	public static final fun minimumSpanningForest (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;)Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;
-	public static final fun shortestPathDijkstra-9scIZJg (Lio/github/alexandrepiveteau/graphs/Network;I)Lio/github/alexandrepiveteau/graphs/DirectedNetwork;
-	public static final fun shortestPathDijkstra-SPb1_vQ (Lio/github/alexandrepiveteau/graphs/Network;II)[I
-	public static final fun shortestPathFasterAlgorithm-9scIZJg (Lio/github/alexandrepiveteau/graphs/Network;I)Lio/github/alexandrepiveteau/graphs/DirectedNetwork;
-	public static final fun shortestPathFasterAlgorithm-SPb1_vQ (Lio/github/alexandrepiveteau/graphs/Network;II)[I
-	public static final fun stronglyConnectedComponentsKosaraju (Lio/github/alexandrepiveteau/graphs/DirectedGraph;)Lkotlin/Pair;
-	public static final fun topologicalSort (Lio/github/alexandrepiveteau/graphs/DirectedGraph;)[I
+	public static final fun connectedComponents (Lio/github/alexandrepiveteau/graphs/Undirected;)Lkotlin/Pair;
+	public static final fun maxFlowEdmondsKarp-SPb1_vQ (Lio/github/alexandrepiveteau/graphs/Directed;II)Lio/github/alexandrepiveteau/graphs/DirectedNetwork;
+	public static final fun minimumSpanningForest (Lio/github/alexandrepiveteau/graphs/Undirected;)Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;
+	public static final fun shortestPathDijkstra-9scIZJg (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;I)Lio/github/alexandrepiveteau/graphs/DirectedNetwork;
+	public static final fun shortestPathDijkstra-SPb1_vQ (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;II)[I
+	public static final fun shortestPathFasterAlgorithm-9scIZJg (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;I)Lio/github/alexandrepiveteau/graphs/DirectedNetwork;
+	public static final fun shortestPathFasterAlgorithm-SPb1_vQ (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;II)[I
+	public static final fun stronglyConnectedComponentsKosaraju (Lio/github/alexandrepiveteau/graphs/Directed;)Lkotlin/Pair;
+	public static final fun topologicalSort (Lio/github/alexandrepiveteau/graphs/Directed;)[I
+}
+
+public final class io/github/alexandrepiveteau/graphs/algorithms/RandomWalkKt {
+	public static final fun randomWalk-YQfbarM (Lio/github/alexandrepiveteau/graphs/Successors;ILkotlin/random/Random;Lkotlin/jvm/functions/Function1;)V
+	public static synthetic fun randomWalk-YQfbarM$default (Lio/github/alexandrepiveteau/graphs/Successors;ILkotlin/random/Random;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
+	public static final fun randomWalkWeighted-YQfbarM (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;ILkotlin/random/Random;Lkotlin/jvm/functions/Function1;)V
+	public static synthetic fun randomWalkWeighted-YQfbarM$default (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;ILkotlin/random/Random;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
 }
 
 public final class io/github/alexandrepiveteau/graphs/algorithms/Traversals {
-	public static final fun forEachArc (Lio/github/alexandrepiveteau/graphs/DirectedGraph;Lkotlin/jvm/functions/Function1;)V
-	public static final fun forEachArc (Lio/github/alexandrepiveteau/graphs/DirectedNetwork;Lkotlin/jvm/functions/Function2;)V
-	public static final fun forEachEdge (Lio/github/alexandrepiveteau/graphs/UndirectedGraph;Lkotlin/jvm/functions/Function1;)V
-	public static final fun forEachEdge (Lio/github/alexandrepiveteau/graphs/UndirectedNetwork;Lkotlin/jvm/functions/Function2;)V
-	public static final fun forEachNeighbor-zrzjTAw (Lio/github/alexandrepiveteau/graphs/Graph;ILkotlin/jvm/functions/Function1;)V
-	public static final fun forEachNeighbor-zrzjTAw (Lio/github/alexandrepiveteau/graphs/Network;ILkotlin/jvm/functions/Function2;)V
-	public static final fun forEachVertex (Lio/github/alexandrepiveteau/graphs/Graph;Lkotlin/jvm/functions/Function1;)V
-	public static final fun forEachVertexBreadthFirst-zrzjTAw (Lio/github/alexandrepiveteau/graphs/Graph;ILkotlin/jvm/functions/Function1;)V
-	public static final fun forEachVertexDepthFirst-YQfbarM (Lio/github/alexandrepiveteau/graphs/Graph;I[ZLkotlin/jvm/functions/Function1;)V
-	public static synthetic fun forEachVertexDepthFirst-YQfbarM$default (Lio/github/alexandrepiveteau/graphs/Graph;I[ZLkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
-	public static final fun forEachVertexDepthFirstHelper-wZYKThQ (Lio/github/alexandrepiveteau/graphs/Graph;I[ZLkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function1;)V
-	public static synthetic fun forEachVertexDepthFirstHelper-wZYKThQ$default (Lio/github/alexandrepiveteau/graphs/Graph;I[ZLkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
-	public static final fun forEachVertexDepthFirstPostOrder-YQfbarM (Lio/github/alexandrepiveteau/graphs/Graph;I[ZLkotlin/jvm/functions/Function1;)V
-	public static synthetic fun forEachVertexDepthFirstPostOrder-YQfbarM$default (Lio/github/alexandrepiveteau/graphs/Graph;I[ZLkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
-	public static final fun shortestPathBreadthFirst-SPb1_vQ (Lio/github/alexandrepiveteau/graphs/Graph;II)[I
+	public static final fun forEachArc (Lio/github/alexandrepiveteau/graphs/Directed;Lkotlin/jvm/functions/Function1;)V
+	public static final fun forEachArc (Lio/github/alexandrepiveteau/graphs/Directed;Lkotlin/jvm/functions/Function2;)V
+	public static final fun forEachEdge (Lio/github/alexandrepiveteau/graphs/Undirected;Lkotlin/jvm/functions/Function1;)V
+	public static final fun forEachEdge (Lio/github/alexandrepiveteau/graphs/Undirected;Lkotlin/jvm/functions/Function2;)V
+	public static final fun forEachSuccessor-zrzjTAw (Lio/github/alexandrepiveteau/graphs/Successors;ILkotlin/jvm/functions/Function1;)V
+	public static final fun forEachSuccessor-zrzjTAw (Lio/github/alexandrepiveteau/graphs/SuccessorsWeight;ILkotlin/jvm/functions/Function2;)V
+	public static final fun forEachVertex (Lio/github/alexandrepiveteau/graphs/VertexSet;Lkotlin/jvm/functions/Function1;)V
+	public static final fun forEachVertexBreadthFirst-zrzjTAw (Lio/github/alexandrepiveteau/graphs/Successors;ILkotlin/jvm/functions/Function1;)V
+	public static final fun forEachVertexDepthFirst-YQfbarM (Lio/github/alexandrepiveteau/graphs/Successors;I[ZLkotlin/jvm/functions/Function1;)V
+	public static synthetic fun forEachVertexDepthFirst-YQfbarM$default (Lio/github/alexandrepiveteau/graphs/Successors;I[ZLkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
+	public static final fun forEachVertexDepthFirstHelper-wZYKThQ (Lio/github/alexandrepiveteau/graphs/Successors;I[ZLkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function1;)V
+	public static synthetic fun forEachVertexDepthFirstHelper-wZYKThQ$default (Lio/github/alexandrepiveteau/graphs/Successors;I[ZLkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
+	public static final fun forEachVertexDepthFirstPostOrder-YQfbarM (Lio/github/alexandrepiveteau/graphs/Successors;I[ZLkotlin/jvm/functions/Function1;)V
+	public static synthetic fun forEachVertexDepthFirstPostOrder-YQfbarM$default (Lio/github/alexandrepiveteau/graphs/Successors;I[ZLkotlin/jvm/functions/Function1;ILjava/lang/Object;)V
+	public static final fun shortestPathBreadthFirst-SPb1_vQ (Lio/github/alexandrepiveteau/graphs/Successors;II)[I
 }
 
 public abstract interface class io/github/alexandrepiveteau/graphs/builder/DirectedGraphBuilder : io/github/alexandrepiveteau/graphs/MutableDirectedGraphScope, io/github/alexandrepiveteau/graphs/builder/GraphBuilder {
@@ -502,11 +572,13 @@ public final class io/github/alexandrepiveteau/graphs/internal/collections/IntDe
 
 public final class io/github/alexandrepiveteau/graphs/internal/collections/IntVector {
 	public fun <init> ()V
+	public final fun clear ()V
 	public final fun get (I)I
 	public final fun getSize ()I
 	public final fun plusAssign (I)V
 	public final fun removeLast ()V
 	public final fun set (II)V
+	public final fun sum ()I
 	public final fun toIntArray ()[I
 }
 
diff --git a/build.gradle.kts b/build.gradle.kts
index f14c616..1f42567 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -1,9 +1,9 @@
 import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 
 plugins {
-  kotlin("multiplatform") version "1.8.20"
-  id("org.jetbrains.kotlinx.binary-compatibility-validator") version "0.13.0"
-  id("org.jetbrains.dokka") version "1.8.10"
+  kotlin("multiplatform") version "1.9.21"
+  id("org.jetbrains.kotlinx.binary-compatibility-validator") version "0.13.2"
+  id("org.jetbrains.dokka") version "1.9.10"
   id("com.vanniktech.maven.publish") version "0.25.2"
 }
 
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Directed.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Directed.kt
new file mode 100644
index 0000000..c50da2c
--- /dev/null
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Directed.kt
@@ -0,0 +1,8 @@
+package io.github.alexandrepiveteau.graphs
+
+/** A marker interface for [Graph]s that are directed. */
+public interface Directed {
+
+  /** Returns true if the given [arc] is contained in this [Directed] graph, and false otherwise. */
+  public operator fun contains(arc: Arc): Boolean
+}
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/DirectedGraph.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/DirectedGraph.kt
index 0a29e6c..6e55197 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/DirectedGraph.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/DirectedGraph.kt
@@ -6,10 +6,7 @@ import io.github.alexandrepiveteau.graphs.builder.buildDirectedGraph
 import io.github.alexandrepiveteau.graphs.builder.buildUndirectedGraph
 
 /** A [DirectedGraph] is a [Graph] where [Vertex]s are linked using [Arc]s. */
-public interface DirectedGraph : Graph {
-
-  /** Returns true if the given [arc] is contained in this [DirectedGraph], and false otherwise. */
-  public operator fun contains(arc: Arc): Boolean
+public interface DirectedGraph : Graph, Directed {
 
   /**
    * An object which serves as the companion of [DirectedGraph], and which provides a number of
@@ -22,13 +19,15 @@ public interface DirectedGraph : Graph {
  * Transforms the [DirectedGraph] into an [UndirectedGraph], by adding an edge between each pair of
  * vertices that are connected by an arc.
  */
-public fun DirectedGraph.toUndirectedGraph(): UndirectedGraph = buildUndirectedGraph {
-  forEachVertex { addVertex() }
-  forEachArc { (u, v) -> addEdge(u edgeTo v) }
-}
+public fun <G> G.toUndirectedGraph(): UndirectedGraph where G : Directed, G : Successors =
+    buildUndirectedGraph {
+      forEachVertex { addVertex() }
+      forEachArc { (u, v) -> addEdge(u edgeTo v) }
+    }
 
 /** Returns the transposed [DirectedGraph], where the direction of arcs has been reversed. */
-public fun DirectedGraph.transposed(): DirectedGraph = buildDirectedGraph {
-  forEachVertex { addVertex() }
-  forEachArc { addArc(it.reversed()) }
-}
+public fun <G> G.transposed(): DirectedGraph where G : Directed, G : Successors =
+    buildDirectedGraph {
+      forEachVertex { addVertex() }
+      forEachArc { addArc(it.reversed()) }
+    }
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/DirectedNetwork.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/DirectedNetwork.kt
index 8d8ed52..9e1f0f3 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/DirectedNetwork.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/DirectedNetwork.kt
@@ -3,17 +3,19 @@ package io.github.alexandrepiveteau.graphs
 /** A [DirectedNetwork] is a [Network] and a [DirectedGraph]. */
 public interface DirectedNetwork : Network, DirectedGraph {
 
-  /**
-   * Returns the weight of the [Arc].
-   *
-   * @throws NoSuchVertexException if [arc] is not a valid arc for this [UndirectedNetwork].
-   * @throws NoSuchEdgeException if there is no arc between the two vertices.
-   */
-  public fun weight(arc: Arc): Int = weight(arc.from, arc.to)
-
   /**
    * An object which serves as the companion of the [DirectedNetwork], and which provides a number
    * of methods to create [DirectedNetwork]s.
    */
   public companion object
 }
+
+/**
+ * Returns the weight of the [Arc].
+ *
+ * @throws NoSuchVertexException if [arc] is not a valid arc for this [UndirectedNetwork].
+ * @throws NoSuchEdgeException if there is no arc between the two vertices.
+ */
+public fun <N> N.successorWeight(
+    arc: Arc,
+): Int where N : Directed, N : SuccessorsWeight = successorWeight(arc.from, arc.to)
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Graph.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Graph.kt
index dd1f1d9..8198c7e 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Graph.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Graph.kt
@@ -8,53 +8,4 @@ package io.github.alexandrepiveteau.graphs
  * links by their index. This is useful for algorithms which need to iterate over the vertices and
  * links of the graph without having to create an explicit iterator.
  */
-public interface Graph {
-
-  /** The number of vertices in this [Graph]. */
-  public val size: Int
-
-  /** Returns true if the given [vertex] is contained in this [Graph], and false otherwise. */
-  public operator fun contains(vertex: Vertex): Boolean = index(vertex) in 0 until size
-
-  /**
-   * Returns the index of the given [vertex] in this [Graph]. If the vertex is not contained in this
-   * [Graph], a [NoSuchVertexException] is thrown.
-   */
-  public fun index(vertex: Vertex): Int
-
-  /**
-   * Returns the [Vertex] at the given [index] in this [Graph]. If the index is not contained in
-   * this [Graph], an [IndexOutOfBoundsException] is thrown.
-   */
-  public fun vertex(index: Int): Vertex
-
-  /**
-   * Returns the number of edges leaving the [Vertex] at the given index in this [Graph]. If the
-   * vertex is not contained in this [Graph], an [IndexOutOfBoundsException] is thrown.
-   */
-  public fun successorsSize(index: Int): Int
-
-  /**
-   * Returns the number of edges leaving the given [vertex] in this [Graph]. If the vertex is not
-   * contained in this [Graph], a [NoSuchVertexException] is thrown.
-   */
-  public fun successorsSize(vertex: Vertex): Int = successorsSize(index(vertex))
-
-  /**
-   * Returns the [Vertex] at the given [neighborIndex] index in the list of neighbors of the
-   * [Vertex] at the given [index] in this [Graph]. If the vertex is not contained in this [Graph],
-   * an [IndexOutOfBoundsException] is thrown.
-   */
-  public fun successor(index: Int, neighborIndex: Int): Vertex
-
-  /**
-   * Returns the [Vertex] at the given [neighborIndex] index in the list of neighbors of the given
-   * [vertex] in this [Graph]. If the vertex is not contained in this [Graph], a
-   * [NoSuchVertexException], and if the neighbor index is not contained in the list of neighbors of
-   * the vertex, an [IndexOutOfBoundsException] is thrown.
-   */
-  public fun successor(
-      vertex: Vertex,
-      neighborIndex: Int,
-  ): Vertex = successor(index(vertex), neighborIndex)
-}
+public interface Graph : VertexSet, Successors
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Network.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Network.kt
index ed59fb6..c5cc12f 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Network.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Network.kt
@@ -4,37 +4,4 @@ package io.github.alexandrepiveteau.graphs
  * A [Network] is a [Graph] with some weights associated to each link. The weights are represented
  * as [Int] values.
  */
-public interface Network : Graph {
-
-  /**
-   * Returns the weight of the edge between the [Vertex] at [index] and the [Vertex] at
-   * [neighborIndex].
-   *
-   * @throws IndexOutOfBoundsException if [index] or [neighborIndex] are not valid indices.
-   */
-  public fun weight(index: Int, neighborIndex: Int): Int
-
-  /**
-   * Returns the weight of the edge between the [Vertex] at [index] and its [neighbor].
-   *
-   * @throws IndexOutOfBoundsException if [index] is not a valid index.
-   * @throws NoSuchVertexException if [neighbor] is not a valid vertex.
-   */
-  public fun weight(index: Int, neighbor: Vertex): Int
-
-  /**
-   * Returns the weight of the edge between the [vertex] and its [neighbor].
-   *
-   * @throws NoSuchVertexException if [vertex] or [neighbor] are not valid vertices.
-   * @throws NoSuchEdgeException if there is no edge between [vertex] and [neighbor].
-   */
-  public fun weight(vertex: Vertex, neighbor: Vertex): Int = weight(index(vertex), neighbor)
-
-  /**
-   * Returns the weight of the edge between the [vertex] and the [Vertex] at [neighborIndex].
-   *
-   * @throws NoSuchVertexException if [vertex] is not a valid vertex.
-   * @throws IndexOutOfBoundsException if [neighborIndex] is not a valid index.
-   */
-  public fun weight(vertex: Vertex, neighborIndex: Int): Int = weight(index(vertex), neighborIndex)
-}
+public interface Network : Graph, SuccessorsWeight
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Predecessors.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Predecessors.kt
new file mode 100644
index 0000000..082c0fc
--- /dev/null
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Predecessors.kt
@@ -0,0 +1,38 @@
+package io.github.alexandrepiveteau.graphs
+
+/**
+ * [Predecessors] are a [VertexSet] where each [Vertex] has a list of neighbors, which can be
+ * accessed by their index.
+ */
+public interface Predecessors : VertexSet {
+
+  /**
+   * Returns the number of edges entering the [Vertex] at the given index in this [Predecessors]. If
+   * the vertex is not contained in this [Predecessors], an [IndexOutOfBoundsException] is thrown.
+   */
+  public fun predecessorsSize(index: Int): Int
+
+  /**
+   * Returns the number of edges entering the given [vertex] in this [Predecessors]. If the vertex
+   * is not contained in this [Predecessors], a [NoSuchVertexException] is thrown.
+   */
+  public fun predecessorsSize(vertex: Vertex): Int = predecessorsSize(index(vertex))
+
+  /**
+   * Returns the [Vertex] at the given [neighborIndex] index in the list of neighbors of the
+   * [Vertex] at the given [index] in this [Predecessors]. If the vertex is not contained in this
+   * [Predecessors], an [IndexOutOfBoundsException] is thrown.
+   */
+  public fun predecessor(index: Int, neighborIndex: Int): Vertex
+
+  /**
+   * Returns the [Vertex] at the given [neighborIndex] index in the list of neighbors of the given
+   * [vertex] in this [Predecessors]. If the vertex is not contained in this [Predecessors], a
+   * [NoSuchVertexException], and if the neighbor index is not contained in the list of neighbors of
+   * the vertex, an [IndexOutOfBoundsException] is thrown.
+   */
+  public fun predecessor(
+      vertex: Vertex,
+      neighborIndex: Int,
+  ): Vertex = predecessor(index(vertex), neighborIndex)
+}
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Successors.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Successors.kt
new file mode 100644
index 0000000..8bdaec1
--- /dev/null
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Successors.kt
@@ -0,0 +1,56 @@
+package io.github.alexandrepiveteau.graphs
+
+/**
+ * [Successors] are a [VertexSet] where each [Vertex] has a list of neighbors, which can be accessed
+ * by their index.
+ */
+public interface Successors : VertexSet {
+
+  /**
+   * Returns the number of edges leaving the [Vertex] at the given index in this [Successors]. If
+   * the vertex is not contained in this [Successors], an [IndexOutOfBoundsException] is thrown.
+   */
+  public fun successorsSize(index: Int): Int
+
+  /**
+   * Returns the number of edges leaving the given [vertex] in this [Successors]. If the vertex is
+   * not contained in this [Successors], a [NoSuchVertexException] is thrown.
+   */
+  public fun successorsSize(vertex: Vertex): Int = successorsSize(index(vertex))
+
+  /**
+   * Returns the index of the vertex at the given [neighborIndex] index in the list of neighbors of
+   * the [Vertex] in this [Successors]. If the vertex is not contained in this [Successors], an
+   * [IndexOutOfBoundsException] is thrown.
+   */
+  public fun successorIndex(index: Int, neighborIndex: Int): Int
+
+  /**
+   * Returns the index of the vertex at the given [neighborIndex] index in the list of neighbors of
+   * the [Vertex] in this [Successors]. If the vertex is not contained in this [Successors], a
+   * [NoSuchVertexException], and if the neighbor index is not contained in the list of neighbors of
+   * the vertex, an [IndexOutOfBoundsException] is thrown.
+   */
+  public fun successorIndex(
+      vertex: Vertex,
+      neighborIndex: Int,
+  ): Int = successorIndex(index(vertex), neighborIndex)
+
+  /**
+   * Returns the [Vertex] at the given [neighborIndex] index in the list of neighbors of the
+   * [Vertex] at the given [index] in this [Successors]. If the vertex is not contained in this
+   * [Successors], an [IndexOutOfBoundsException] is thrown.
+   */
+  public fun successorVertex(index: Int, neighborIndex: Int): Vertex
+
+  /**
+   * Returns the [Vertex] at the given [neighborIndex] index in the list of neighbors of the given
+   * [vertex] in this [Successors]. If the vertex is not contained in this [Successors], a
+   * [NoSuchVertexException], and if the neighbor index is not contained in the list of neighbors of
+   * the vertex, an [IndexOutOfBoundsException] is thrown.
+   */
+  public fun successorVertex(
+      vertex: Vertex,
+      neighborIndex: Int,
+  ): Vertex = successorVertex(index(vertex), neighborIndex)
+}
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/SuccessorsWeight.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/SuccessorsWeight.kt
new file mode 100644
index 0000000..07ef077
--- /dev/null
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/SuccessorsWeight.kt
@@ -0,0 +1,42 @@
+package io.github.alexandrepiveteau.graphs
+
+/**
+ * [SuccessorsWeight] are a [Successors] where each link has a weight, which can be accessed by
+ * their index.
+ */
+public interface SuccessorsWeight : Successors {
+
+  /**
+   * Returns the weight of the edge between the [Vertex] at [index] and the [Vertex] at
+   * [neighborIndex].
+   *
+   * @throws IndexOutOfBoundsException if [index] or [neighborIndex] are not valid indices.
+   */
+  public fun successorWeight(index: Int, neighborIndex: Int): Int
+
+  /**
+   * Returns the weight of the edge between the [Vertex] at [index] and its [neighbor].
+   *
+   * @throws IndexOutOfBoundsException if [index] is not a valid index.
+   * @throws NoSuchVertexException if [neighbor] is not a valid vertex.
+   */
+  public fun successorWeight(index: Int, neighbor: Vertex): Int
+
+  /**
+   * Returns the weight of the edge between the [vertex] and its [neighbor].
+   *
+   * @throws NoSuchVertexException if [vertex] or [neighbor] are not valid vertices.
+   * @throws NoSuchEdgeException if there is no edge between [vertex] and [neighbor].
+   */
+  public fun successorWeight(vertex: Vertex, neighbor: Vertex): Int =
+      successorWeight(index(vertex), neighbor)
+
+  /**
+   * Returns the weight of the edge between the [vertex] and the [Vertex] at [neighborIndex].
+   *
+   * @throws NoSuchVertexException if [vertex] is not a valid vertex.
+   * @throws IndexOutOfBoundsException if [neighborIndex] is not a valid index.
+   */
+  public fun successorWeight(vertex: Vertex, neighborIndex: Int): Int =
+      successorWeight(index(vertex), neighborIndex)
+}
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Undirected.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Undirected.kt
new file mode 100644
index 0000000..b67f43a
--- /dev/null
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/Undirected.kt
@@ -0,0 +1,8 @@
+package io.github.alexandrepiveteau.graphs
+
+/** A marker interface for [Graph]s that are undirected. */
+public interface Undirected {
+
+  /** Returns true if the given [edge] is contained in this [Undirected] graph, and false otherwise. */
+  public operator fun contains(edge: Edge): Boolean
+}
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.complete.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.complete.kt
index b7e1cd3..82bf5fe 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.complete.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.complete.kt
@@ -2,13 +2,22 @@ package io.github.alexandrepiveteau.graphs
 
 /** An implementation of [UndirectedGraph] which is empty. */
 private object EmptyUndirectedGraph : UndirectedGraph {
+
   override val size = 0
+
   override fun contains(vertex: Vertex) = false
+
   override fun contains(edge: Edge) = false
+
   override fun index(vertex: Vertex) = throw NoSuchVertexException()
+
   override fun vertex(index: Int) = throw IndexOutOfBoundsException()
+
   override fun successorsSize(index: Int) = throw IndexOutOfBoundsException()
-  override fun successor(index: Int, neighborIndex: Int) = throw IndexOutOfBoundsException()
+
+  override fun successorIndex(index: Int, neighborIndex: Int) = throw IndexOutOfBoundsException()
+
+  override fun successorVertex(index: Int, neighborIndex: Int) = throw IndexOutOfBoundsException()
 }
 
 /** Returns an empty [UndirectedGraph], which is a graph with no vertices and no edges. */
@@ -16,8 +25,10 @@ public fun UndirectedGraph.Companion.empty(): UndirectedGraph = EmptyUndirectedG
 
 /** An implementation of [UndirectedNetwork] which is empty. */
 private object EmptyUndirectedNetwork : UndirectedNetwork, UndirectedGraph by EmptyUndirectedGraph {
-  override fun weight(index: Int, neighborIndex: Int) = throw IndexOutOfBoundsException()
-  override fun weight(index: Int, neighbor: Vertex) = throw IndexOutOfBoundsException()
+
+  override fun successorWeight(index: Int, neighborIndex: Int) = throw IndexOutOfBoundsException()
+
+  override fun successorWeight(index: Int, neighbor: Vertex) = throw IndexOutOfBoundsException()
 }
 
 /** Returns an empty [UndirectedNetwork], which is a network with no vertices and no edges. */
@@ -25,28 +36,37 @@ public fun UndirectedNetwork.Companion.empty(): UndirectedNetwork = EmptyUndirec
 
 /** An implementation of a [UndirectedGraph] which is complete. */
 private open class CompleteUndirectedGraph(override val size: Int) : UndirectedGraph {
+
   override fun contains(edge: Edge): Boolean {
     val (u, v) = edge
     return u != v && u in this && v in this
   }
+
   override fun index(vertex: Vertex): Int {
     if (vertex.index < 0 || vertex.index >= size) throw NoSuchVertexException()
     return vertex.index
   }
+
   override fun vertex(index: Int): Vertex {
     if (index < 0 || index >= size) throw IndexOutOfBoundsException()
     return Vertex(index)
   }
+
   override fun successorsSize(index: Int): Int {
     if (index < 0 || index >= size) throw IndexOutOfBoundsException()
     return size - 1
   }
-  override fun successor(index: Int, neighborIndex: Int): Vertex {
+
+  override fun successorIndex(index: Int, neighborIndex: Int): Int {
     if (index < 0 || index >= size) throw IndexOutOfBoundsException()
     if (neighborIndex < 0 || neighborIndex >= size - 1) throw IndexOutOfBoundsException()
     var vertex = neighborIndex
     if (vertex >= index) vertex++
-    return Vertex(vertex)
+    return vertex
+  }
+
+  override fun successorVertex(index: Int, neighborIndex: Int): Vertex {
+    return vertex(successorIndex(index, neighborIndex))
   }
 }
 
@@ -68,13 +88,13 @@ public fun UndirectedGraph.Companion.complete(size: Int): UndirectedGraph {
 private class CompleteUndirectedNetwork(size: Int, private val weight: Int) :
     CompleteUndirectedGraph(size), UndirectedNetwork {
 
-  override fun weight(index: Int, neighborIndex: Int): Int {
+  override fun successorWeight(index: Int, neighborIndex: Int): Int {
     if (index < 0 || index >= size) throw IndexOutOfBoundsException()
     if (neighborIndex < 0 || neighborIndex >= size - 1) throw IndexOutOfBoundsException()
     return weight
   }
 
-  override fun weight(index: Int, neighbor: Vertex): Int {
+  override fun successorWeight(index: Int, neighbor: Vertex): Int {
     if (index < 0 || index >= size) throw IndexOutOfBoundsException()
     if (neighbor.index < 0 || neighbor.index >= size) throw NoSuchVertexException()
     if (index == neighbor.index) throw NoSuchEdgeException()
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.kt
index 36a890c..e6ed6f5 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.kt
@@ -5,12 +5,7 @@ import io.github.alexandrepiveteau.graphs.algorithms.forEachVertex
 import io.github.alexandrepiveteau.graphs.builder.buildDirectedGraph
 
 /** A [UndirectedGraph] is a [Graph] where [Vertex]s are linked using [Edge]s. */
-public interface UndirectedGraph : Graph {
-
-  /**
-   * Returns true if the given [edge] is contained in this [UndirectedGraph], and false otherwise.
-   */
-  public operator fun contains(edge: Edge): Boolean
+public interface UndirectedGraph : Graph, Undirected {
 
   /**
    * An object which serves as the companion of [UndirectedGraph], and which provides a number of
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedNetwork.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedNetwork.kt
index b754b65..d57d766 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedNetwork.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/UndirectedNetwork.kt
@@ -9,7 +9,7 @@ public interface UndirectedNetwork : Network, UndirectedGraph {
    * @throws NoSuchVertexException if [edge] is not a valid edge for this [UndirectedNetwork].
    * @throws NoSuchEdgeException if there is no edge between the two vertices.
    */
-  public fun weight(edge: Edge): Int = weight(edge.component1(), edge.component2())
+  public fun weight(edge: Edge): Int = successorWeight(edge.component1(), edge.component2())
 
   /**
    * An object which serves as the companion of the [UndirectedNetwork], and which provides a number
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/VertexMap.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/VertexMap.kt
index 3bf26e5..1cfef3e 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/VertexMap.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/VertexMap.kt
@@ -15,7 +15,7 @@ public inline fun VertexMap(
     init: (index: Vertex) -> Vertex,
 ): VertexMap {
   return VertexMap(size).apply {
-    for (index in 0 until size) {
+    for (index in 0 ..< size) {
       this[Vertex(index)] = init(Vertex(index))
     }
   }
@@ -77,7 +77,7 @@ public value class VertexMap private constructor(private val array: VertexArray)
  * @receiver the [VertexMap] to iterate over.
  */
 public inline fun VertexMap.forEach(action: (Vertex, Vertex) -> Unit) {
-  for (index in 0 until size) {
+  for (index in 0 ..< size) {
     val v = Vertex(index)
     action(v, this[v])
   }
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/VertexSet.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/VertexSet.kt
new file mode 100644
index 0000000..e2da819
--- /dev/null
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/VertexSet.kt
@@ -0,0 +1,23 @@
+package io.github.alexandrepiveteau.graphs
+
+/** A set of vertices. Vertices can be iterated over, and their [size] can be queried. */
+public interface VertexSet {
+
+  /** The number of vertices in this [VertexSet]. */
+  public val size: Int
+
+  /** Returns true if the given [vertex] is contained in this [VertexSet], and false otherwise. */
+  public operator fun contains(vertex: Vertex): Boolean = index(vertex) in 0 ..< size
+
+  /**
+   * Returns the index of the given [vertex] in this [VertexSet]. If the vertex is not contained in
+   * this [VertexSet], a [NoSuchVertexException] is thrown.
+   */
+  public fun index(vertex: Vertex): Int
+
+  /**
+   * Returns the [Vertex] at the given [index] in this [VertexSet]. If the index is not contained in
+   * this [VertexSet], an [IndexOutOfBoundsException] is thrown.
+   */
+  public fun vertex(index: Int): Vertex
+}
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/BasicTraversal.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/BasicTraversal.kt
index abd594e..3cdd10e 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/BasicTraversal.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/BasicTraversal.kt
@@ -15,9 +15,11 @@ import kotlin.jvm.JvmName
  * - **Time complexity**: O(|N|), where |N| is the number of vertices in this graph.
  * - **Space complexity**: O(1).
  */
-public inline fun Graph.forEachVertex(action: (Vertex) -> Unit) {
+public inline fun <G> G.forEachVertex(
+    action: (Vertex) -> Unit,
+) where G : VertexSet {
   contract { callsInPlace(action) }
-  for (i in 0 until size) action(vertex(i))
+  for (i in 0 ..< size) action(vertex(i))
 }
 
 /**
@@ -27,10 +29,13 @@ public inline fun Graph.forEachVertex(action: (Vertex) -> Unit) {
  * - **Time complexity**: O(|N|), where |N| is the number of neighbors of the given [vertex].
  * - **Space complexity**: O(1).
  */
-public inline fun Graph.forEachNeighbor(vertex: Vertex, action: (Vertex) -> Unit) {
+public inline fun <G> G.forEachSuccessor(
+    vertex: Vertex,
+    action: (Vertex) -> Unit,
+) where G : Successors {
   contract { callsInPlace(action) }
   val index = index(vertex)
-  for (i in 0 until successorsSize(index)) action(successor(vertex, i))
+  for (i in 0 ..< successorsSize(index)) action(successorVertex(vertex, i))
 }
 
 /**
@@ -40,10 +45,13 @@ public inline fun Graph.forEachNeighbor(vertex: Vertex, action: (Vertex) -> Unit
  * - **Time complexity**: O(|N|), where |N| is the number of neighbors of the given [vertex].
  * - **Space complexity**: O(1).
  */
-public inline fun Network.forEachNeighbor(vertex: Vertex, action: (Vertex, Int) -> Unit) {
+public inline fun <N> N.forEachSuccessor(
+    vertex: Vertex,
+    action: (Vertex, Int) -> Unit,
+) where N : SuccessorsWeight {
   contract { callsInPlace(action) }
   val index = index(vertex)
-  for (i in 0 until successorsSize(index)) action(successor(vertex, i), weight(vertex, i))
+  for (i in 0 ..< successorsSize(index)) action(successorVertex(vertex, i), successorWeight(vertex, i))
 }
 
 /**
@@ -53,9 +61,11 @@ public inline fun Network.forEachNeighbor(vertex: Vertex, action: (Vertex, Int)
  * - **Time complexity**: O(|A|), where |A| is the number of arcs in this graph.
  * - **Space complexity**: O(1).
  */
-public inline fun DirectedGraph.forEachArc(action: (Arc) -> Unit) {
+public inline fun <G> G.forEachArc(
+    action: (Arc) -> Unit,
+) where G : Directed, G : Successors {
   contract { callsInPlace(action) }
-  forEachVertex { u -> forEachNeighbor(u) { v -> action(u arcTo v) } }
+  forEachVertex { u -> forEachSuccessor(u) { v -> action(u arcTo v) } }
 }
 
 /**
@@ -65,9 +75,11 @@ public inline fun DirectedGraph.forEachArc(action: (Arc) -> Unit) {
  * - **Time complexity**: O(|A|), where |A| is the number of arcs in this graph.
  * - **Space complexity**: O(1).
  */
-public inline fun DirectedNetwork.forEachArc(action: (Arc, Int) -> Unit) {
+public inline fun <N> N.forEachArc(
+    action: (Arc, Int) -> Unit,
+) where N : Directed, N : SuccessorsWeight {
   contract { callsInPlace(action) }
-  forEachVertex { u -> forEachNeighbor(u) { v, w -> action(u arcTo v, w) } }
+  forEachVertex { u -> forEachSuccessor(u) { v, w -> action(u arcTo v, w) } }
 }
 
 /**
@@ -77,9 +89,11 @@ public inline fun DirectedNetwork.forEachArc(action: (Arc, Int) -> Unit) {
  * - **Time complexity**: O(|E|), where |E| is the number of edges in this graph.
  * - **Space complexity**: O(1).
  */
-public inline fun UndirectedGraph.forEachEdge(action: (Edge) -> Unit) {
+public inline fun <G> G.forEachEdge(
+    action: (Edge) -> Unit,
+) where G : Undirected, G : Successors {
   contract { callsInPlace(action) }
-  forEachVertex { u -> forEachNeighbor(u) { v -> if (index(u) <= index(v)) action(u edgeTo v) } }
+  forEachVertex { u -> forEachSuccessor(u) { v -> if (index(u) <= index(v)) action(u edgeTo v) } }
 }
 
 /**
@@ -89,9 +103,11 @@ public inline fun UndirectedGraph.forEachEdge(action: (Edge) -> Unit) {
  * - **Time complexity**: O(|E|), where |E| is the number of edges in this graph.
  * - **Space complexity**: O(1).
  */
-public inline fun UndirectedNetwork.forEachEdge(action: (Edge, Int) -> Unit) {
+public inline fun <N> N.forEachEdge(
+    action: (Edge, Int) -> Unit,
+) where N : Undirected, N : SuccessorsWeight {
   contract { callsInPlace(action) }
   forEachVertex { u ->
-    forEachNeighbor(u) { v, w -> if (index(u) <= index(v)) action(u edgeTo v, w) }
+    forEachSuccessor(u) { v, w -> if (index(u) <= index(v)) action(u edgeTo v, w) }
   }
 }
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/BreadthFirstTraversal.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/BreadthFirstTraversal.kt
index d99d54a..324deb6 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/BreadthFirstTraversal.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/BreadthFirstTraversal.kt
@@ -21,14 +21,17 @@ import kotlin.jvm.JvmName
  * @param from the vertex from which to start the search.
  * @param action the action to execute on each vertex.
  */
-public inline fun Graph.forEachVertexBreadthFirst(from: Vertex, action: (Vertex) -> Unit) {
+public inline fun <G> G.forEachVertexBreadthFirst(
+    from: Vertex,
+    action: (Vertex) -> Unit,
+) where G : Successors {
   contract { callsInPlace(action) }
   val queue = IntDequeue().apply { addLast(index(from)) }
   val visited = BooleanArray(size).apply { this[index(from)] = true }
   while (queue.size > 0) {
     val next = queue.removeFirst()
     action(vertex(next))
-    forEachNeighbor(vertex(next)) {
+    forEachSuccessor(vertex(next)) {
       if (!visited[index(it)]) {
         queue.addLast(index(it))
         visited[index(it)] = true
@@ -51,14 +54,17 @@ public inline fun Graph.forEachVertexBreadthFirst(from: Vertex, action: (Vertex)
  * @return the [VertexArray] with the shortest path going from the [from] vertex to the [to] vertex,
  *   or `null` if there is no path between the two vertices.
  */
-public fun Graph.shortestPathBreadthFirst(from: Vertex, to: Vertex): VertexArray? {
+public fun <G> G.shortestPathBreadthFirst(
+    from: Vertex,
+    to: Vertex,
+): VertexArray? where G : Successors {
   if (from !in this) throw NoSuchVertexException()
   if (to !in this) throw NoSuchVertexException()
 
   val parents = VertexMap(size) { Vertex.Invalid }
 
   forEachVertexBreadthFirst(from) { u ->
-    forEachNeighbor(u) { v ->
+    forEachSuccessor(u) { v ->
       if (parents[v] == Vertex.Invalid) parents[v] = u
       if (v == to) return computePath(parents, from, to)
     }
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ConnectedComponents.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ConnectedComponents.kt
index a036e56..aa1fbf6 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ConnectedComponents.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ConnectedComponents.kt
@@ -3,6 +3,8 @@
 
 package io.github.alexandrepiveteau.graphs.algorithms
 
+import io.github.alexandrepiveteau.graphs.Successors
+import io.github.alexandrepiveteau.graphs.Undirected
 import io.github.alexandrepiveteau.graphs.UndirectedGraph
 import io.github.alexandrepiveteau.graphs.VertexMap
 import io.github.alexandrepiveteau.graphs.builder.buildUndirectedGraph
@@ -19,7 +21,9 @@ import kotlin.jvm.JvmName
  *   of edges in this graph.
  * - **Space complexity**: `O(|N|)`, where |N| is the number of vertices in this graph.
  */
-public fun UndirectedGraph.connectedComponents(): Pair<UndirectedGraph, VertexMap> {
+public fun <G> G.connectedComponents(): Pair<UndirectedGraph, VertexMap> where
+G : Undirected,
+G : Successors {
   val map = VertexMap(size)
   val visited = BooleanArray(size)
   // TODO : We could use a specific implementation of Graph which has no edges between vertices.
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/DepthFirstTraversal.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/DepthFirstTraversal.kt
index 424f24e..81cdad9 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/DepthFirstTraversal.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/DepthFirstTraversal.kt
@@ -3,7 +3,7 @@
 
 package io.github.alexandrepiveteau.graphs.algorithms
 
-import io.github.alexandrepiveteau.graphs.Graph
+import io.github.alexandrepiveteau.graphs.Successors
 import io.github.alexandrepiveteau.graphs.Vertex
 import io.github.alexandrepiveteau.graphs.internal.collections.IntDequeue
 import kotlin.contracts.contract
@@ -23,11 +23,11 @@ import kotlin.jvm.JvmName
  * @param visited the vertices that have already been visited, which will be updated by the search.
  * @param action the action to execute on each vertex.
  */
-public inline fun Graph.forEachVertexDepthFirst(
+public inline fun <G> G.forEachVertexDepthFirst(
     from: Vertex,
     visited: BooleanArray = BooleanArray(size),
     action: (Vertex) -> Unit,
-) {
+) where G : Successors {
   contract { callsInPlace(action) }
   forEachVertexDepthFirstHelper(from, visited, action) {}
 }
@@ -45,11 +45,11 @@ public inline fun Graph.forEachVertexDepthFirst(
  * @param visited the vertices that have already been visited, which will be updated by the search.
  * @param action the action to execute on each vertex.
  */
-public inline fun Graph.forEachVertexDepthFirstPostOrder(
+public inline fun <G> G.forEachVertexDepthFirstPostOrder(
     from: Vertex,
     visited: BooleanArray = BooleanArray(size),
     action: (Vertex) -> Unit,
-) {
+) where G : Successors {
   contract { callsInPlace(action) }
   forEachVertexDepthFirstHelper(from, visited, {}, action)
 }
@@ -70,12 +70,12 @@ public inline fun Graph.forEachVertexDepthFirstPostOrder(
  * @param postOrderAction the action to execute on each vertex post order.
  */
 @PublishedApi
-internal inline fun Graph.forEachVertexDepthFirstHelper(
+internal inline fun <G> G.forEachVertexDepthFirstHelper(
     from: Vertex,
     visited: BooleanArray = BooleanArray(size),
     inOrderAction: (Vertex) -> Unit,
     postOrderAction: (Vertex) -> Unit,
-) {
+) where G : Successors {
   contract {
     callsInPlace(inOrderAction)
     callsInPlace(postOrderAction)
@@ -90,7 +90,7 @@ internal inline fun Graph.forEachVertexDepthFirstHelper(
     }
     var found = false
     while (counts[next] < successorsSize(next)) {
-      val neighbor = successor(next, counts[next]++)
+      val neighbor = successorVertex(next, counts[next]++)
       if (!visited[index(neighbor)]) {
         found = true
         path.addLast(index(neighbor))
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Dijkstra.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Dijkstra.kt
index 92a9eeb..07f4d50 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Dijkstra.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Dijkstra.kt
@@ -14,7 +14,9 @@ import kotlin.jvm.JvmName
  * @param from the [Vertex] to start the search from.
  * @return the map of parents for each vertex in the shortest path tree from the [from] vertex.
  */
-private fun Network.shortestPathDijkstraParents(from: Vertex): VertexMap {
+private fun <N> N.shortestPathDijkstraParents(
+    from: Vertex,
+): VertexMap where N : SuccessorsWeight {
   val parents = VertexMap(size) { Vertex.Invalid }
   val queue = IntMinPriorityQueue(size)
   val distances = IntArray(size) { Int.MAX_VALUE }
@@ -26,7 +28,7 @@ private fun Network.shortestPathDijkstraParents(from: Vertex): VertexMap {
   while (queue.size > 0) {
     val v1 = vertex(queue.remove())
     visited[index(v1)] = true
-    forEachNeighbor(v1) { v2, weight ->
+    forEachSuccessor(v1) { v2, weight ->
       if (!visited[index(v2)]) {
         // Note : we only throw on negative weights if they are visited, so a graph with negative
         //        weights in a component disconnected from the source will not throw.
@@ -61,7 +63,9 @@ private fun Network.shortestPathDijkstraParents(from: Vertex): VertexMap {
  * @throws NoSuchVertexException if the [from] vertex is not in this network.
  * @throws IllegalArgumentException if the network contains negative weights.
  */
-public fun Network.shortestPathDijkstra(from: Vertex): DirectedNetwork {
+public fun <N> N.shortestPathDijkstra(
+    from: Vertex,
+): DirectedNetwork where N : SuccessorsWeight {
   if (from !in this) throw NoSuchVertexException()
   return computeNetwork(shortestPathDijkstraParents(from))
 }
@@ -82,7 +86,10 @@ public fun Network.shortestPathDijkstra(from: Vertex): DirectedNetwork {
  * @throws NoSuchVertexException if the [from] or [to] vertices are not in this graph.
  * @throws IllegalArgumentException if the network contains negative weights.
  */
-public fun Network.shortestPathDijkstra(from: Vertex, to: Vertex): VertexArray? {
+public fun <N> N.shortestPathDijkstra(
+    from: Vertex,
+    to: Vertex,
+): VertexArray? where N : SuccessorsWeight {
   if (from !in this) throw NoSuchVertexException()
   if (to !in this) throw NoSuchVertexException()
   return computePath(shortestPathDijkstraParents(from), from, to)
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/EdmondsKarp.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/EdmondsKarp.kt
index 93a7e9b..15cd657 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/EdmondsKarp.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/EdmondsKarp.kt
@@ -10,13 +10,15 @@ import kotlin.jvm.JvmName
 import kotlin.math.min
 
 /** Returns the residual network of this [DirectedNetwork], given the current [flow]. */
-private fun DirectedNetwork.residual(flow: DirectedNetwork): DirectedNetwork {
+private fun <N> N.residual(
+    flow: DirectedNetwork,
+): DirectedNetwork where N : Directed, N : SuccessorsWeight {
   return buildDirectedNetwork {
     forEachVertex { addVertex() }
     forEachArc { arc ->
-      val forwardCapacity = weight(arc) - flow.weight(arc)
+      val forwardCapacity = successorWeight(arc) - flow.successorWeight(arc)
       if (forwardCapacity > 0) addArc(arc, forwardCapacity)
-      val backwardCapacity = flow.weight(arc)
+      val backwardCapacity = flow.successorWeight(arc)
       if (backwardCapacity > 0) addArc(arc.reversed(), backwardCapacity)
     }
   }
@@ -24,26 +26,34 @@ private fun DirectedNetwork.residual(flow: DirectedNetwork): DirectedNetwork {
 
 /** Iterates over all the arcs in the path, and calls the [action] for each of them. */
 private inline fun VertexArray.forEachArc(action: (Arc) -> Unit) {
-  for (u in 0 until size - 1) {
+  for (u in 0 ..< size - 1) {
     action(this[u] arcTo this[u + 1])
   }
 }
 
 /** Returns the remaining capacity of the [flow] in the [path]. */
-private fun DirectedNetwork.remainingCapacity(flow: DirectedNetwork, path: VertexArray): Int {
+private fun <N> N.remainingCapacity(
+    flow: DirectedNetwork,
+    path: VertexArray,
+): Int where N : Directed, N : SuccessorsWeight {
   var capacity = Int.MAX_VALUE
   path.forEachArc { arc ->
-    val local = if (arc in this) weight(arc) - flow.weight(arc) else flow.weight(arc.reversed())
+    val local =
+        if (arc in this) successorWeight(arc) - flow.successorWeight(arc)
+        else flow.successorWeight(arc.reversed())
     capacity = min(capacity, local)
   }
   return capacity
 }
 
 /** Augments the [flow] with the given [path] and [flow], and returns the new flow. */
-private fun DirectedNetwork.augment(path: VertexArray, flow: Int): DirectedNetwork {
+private fun <N> N.augment(
+    path: VertexArray,
+    flow: Int,
+): DirectedNetwork where N : Directed, N : SuccessorsWeight {
   return buildDirectedNetwork {
     forEachVertex { addVertex() }
-    forEachArc { (u, v) -> addArc(u arcTo v, weight(u arcTo v)) }
+    forEachVertex { u -> forEachSuccessor(u) { v, w -> addArc(u arcTo v, w) } }
     path.forEachArc { arc ->
       if (arc in this@augment) addArc(arc, flow) else addArc(arc.reversed(), -flow)
     }
@@ -60,7 +70,10 @@ private fun DirectedNetwork.augment(path: VertexArray, flow: Int): DirectedNetwo
  *   constrained by the capacities of the arcs.
  * @receiver the [Network] on which to compute the maximum flow.
  */
-public fun DirectedNetwork.maxFlowEdmondsKarp(from: Vertex, to: Vertex): DirectedNetwork {
+public fun <N> N.maxFlowEdmondsKarp(
+    from: Vertex,
+    to: Vertex,
+): DirectedNetwork where N : Directed, N : SuccessorsWeight {
   // TODO : Use some MutableDirectedNetworks once they're implemented.
   var maxFlow = buildDirectedNetwork {
     forEachVertex { addVertex() }
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Kosaraju.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Kosaraju.kt
index 5190180..b03996b 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Kosaraju.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Kosaraju.kt
@@ -16,7 +16,9 @@ import kotlin.jvm.JvmName
  *   connected component.
  * @receiver the [DirectedGraph] to transform.
  */
-public fun DirectedGraph.stronglyConnectedComponentsKosaraju(): Pair<DirectedGraph, VertexMap> {
+public fun <G> G.stronglyConnectedComponentsKosaraju(): Pair<DirectedGraph, VertexMap> where
+G : Directed,
+G : Successors {
   // 1. Traverse all vertices in post-order fashion, and prepend them to the queue.
   val visited = BooleanArray(size)
   val queue = IntDequeue()
@@ -32,7 +34,7 @@ public fun DirectedGraph.stronglyConnectedComponentsKosaraju(): Pair<DirectedGra
   val assigned = BooleanArray(size)
   val order = queue.toIntArray().asVertexArray()
   var nextVertex = 0
-  for (i in 0 until order.size) {
+  for (i in 0 ..< order.size) {
     val v = order[i]
     if (!assigned[index(v)]) {
       transposed.forEachVertexDepthFirst(v, assigned) { components[index(it)] = nextVertex }
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ParentsMap.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ParentsMap.kt
index 2e064a9..f4f8dc2 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ParentsMap.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ParentsMap.kt
@@ -15,7 +15,11 @@ import io.github.alexandrepiveteau.graphs.internal.collections.IntDequeue
  *   the [to] vertex.
  * @receiver the [Graph] on which the traversal was performed.
  */
-internal fun Graph.computePath(parents: VertexMap, from: Vertex, to: Vertex): VertexArray? {
+internal fun <G> G.computePath(
+    parents: VertexMap,
+    from: Vertex,
+    to: Vertex,
+): VertexArray? where G : VertexSet {
   if (from == Vertex.Invalid) throw IllegalArgumentException()
   if (to == Vertex.Invalid) throw IllegalArgumentException()
   val path = IntDequeue()
@@ -36,12 +40,14 @@ internal fun Graph.computePath(parents: VertexMap, from: Vertex, to: Vertex): Ve
  * @return the [DirectedNetwork] for the subgraph of this [Network] defined by the [parents] map.
  * @receiver the [Network] to transform.
  */
-internal fun Network.computeNetwork(parents: VertexMap): DirectedNetwork {
+internal fun <N> N.computeNetwork(
+    parents: VertexMap,
+): DirectedNetwork where N : SuccessorsWeight {
   return buildDirectedNetwork {
     forEachVertex { addVertex() }
     parents.forEach { vertex, parent ->
       if (parent != Vertex.Invalid) {
-        addArc(parent arcTo vertex, weight(parent, vertex))
+        addArc(parent arcTo vertex, successorWeight(parent, vertex))
       }
     }
   }
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Prim.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Prim.kt
index 9d5cc8a..c6a857c 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Prim.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/Prim.kt
@@ -3,11 +3,8 @@
 
 package io.github.alexandrepiveteau.graphs.algorithms
 
-import io.github.alexandrepiveteau.graphs.UndirectedNetwork
-import io.github.alexandrepiveteau.graphs.Vertex
-import io.github.alexandrepiveteau.graphs.VertexMap
+import io.github.alexandrepiveteau.graphs.*
 import io.github.alexandrepiveteau.graphs.builder.buildUndirectedNetwork
-import io.github.alexandrepiveteau.graphs.edgeTo
 import io.github.alexandrepiveteau.graphs.internal.collections.IntMinPriorityQueue
 import kotlin.jvm.JvmMultifileClass
 import kotlin.jvm.JvmName
@@ -19,33 +16,37 @@ import kotlin.jvm.JvmName
  * @return an [UndirectedNetwork] corresponding to the minimum spanning forest of the current
  * @receiver the [UndirectedNetwork] to compute the minimum spanning forest from.
  */
-public fun UndirectedNetwork.minimumSpanningForest(): UndirectedNetwork = buildUndirectedNetwork {
-  // Create all vertices in the resulting forest.
-  repeat(size) { addVertex() }
+public fun <N> N.minimumSpanningForest(): UndirectedNetwork where
+N : Undirected,
+N : SuccessorsWeight {
+  return buildUndirectedNetwork {
+    // Create all vertices in the resulting forest.
+    repeat(size) { addVertex() }
 
-  // Create the state for the Prim algorithm.
-  val parents = VertexMap(size) { Vertex.Invalid }
-  val weights = IntArray(size) { Int.MAX_VALUE }
-  val queue = IntMinPriorityQueue(size)
-  val visited = BooleanArray(size) { false }
+    // Create the state for the Prim algorithm.
+    val parents = VertexMap(size) { Vertex.Invalid }
+    val weights = IntArray(size) { Int.MAX_VALUE }
+    val queue = IntMinPriorityQueue(size)
+    val visited = BooleanArray(size) { false }
 
-  // Iterate over each tree in the forest.
-  forEachVertex { start ->
-    if (!visited[index(start)]) {
-      queue[index(start)] = 0
-      while (queue.size > 0) {
-        val v1 = vertex(queue.remove())
-        visited[index(v1)] = true
-        if (parents[v1] != Vertex.Invalid) {
-          addEdge(v1 edgeTo parents[v1], weights[index(v1)])
-        }
-        forEachNeighbor(v1) { v2, weight ->
-          if (!visited[index(v2)]) {
-            val d = if (queue.contains(index(v2))) queue[index(v2)] else Int.MAX_VALUE
-            if (weight < d) {
-              parents[v2] = v1
-              weights[index(v2)] = weight
-              queue[index(v2)] = weight
+    // Iterate over each tree in the forest.
+    forEachVertex { start ->
+      if (!visited[index(start)]) {
+        queue[index(start)] = 0
+        while (queue.size > 0) {
+          val v1 = vertex(queue.remove())
+          visited[index(v1)] = true
+          if (parents[v1] != Vertex.Invalid) {
+            addEdge(v1 edgeTo parents[v1], weights[index(v1)])
+          }
+          forEachSuccessor(v1) { v2, weight ->
+            if (!visited[index(v2)]) {
+              val d = if (queue.contains(index(v2))) queue[index(v2)] else Int.MAX_VALUE
+              if (weight < d) {
+                parents[v2] = v1
+                weights[index(v2)] = weight
+                queue[index(v2)] = weight
+              }
             }
           }
         }
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/RandomWalk.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/RandomWalk.kt
new file mode 100644
index 0000000..b756f36
--- /dev/null
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/RandomWalk.kt
@@ -0,0 +1,91 @@
+package io.github.alexandrepiveteau.graphs.algorithms
+
+import io.github.alexandrepiveteau.graphs.Successors
+import io.github.alexandrepiveteau.graphs.SuccessorsWeight
+import io.github.alexandrepiveteau.graphs.Vertex
+import io.github.alexandrepiveteau.graphs.internal.collections.IntVector
+import kotlin.contracts.contract
+import kotlin.random.Random
+
+/**
+ * Performs a random walk on the graph, starting from the given [from] vertex, and performs the
+ * given [action] on each vertex. The walk may be infinite if the graph contains cycles, and the
+ * walk will stop if the vertex has no successors.
+ *
+ * This method is inline, so it can be used to traverse the graph with suspending functions.
+ *
+ * ## Asymptotic complexity
+ * - **Time complexity**: Depends on the graph.
+ * - **Space complexity**: O(1).
+ */
+public inline fun <G> G.randomWalk(
+    from: Vertex,
+    random: Random = Random,
+    action: (Vertex) -> Unit,
+) where G : Successors {
+  contract { callsInPlace(action) }
+
+  var current = index(from)
+
+  while (true) {
+    action(vertex(current))
+    val size = successorsSize(current)
+    if (size == 0) return
+
+    current = index(successorVertex(current, random.nextInt(size)))
+  }
+}
+
+/**
+ * Performs a random walk on the graph, starting from the given [from] vertex, and performs the
+ * given [action] on each vertex. The walk may be infinite if the graph contains cycles, and the
+ * walk will stop if the vertex has no successors. The walk will be weighted, and the probability of
+ * choosing a successor is proportional to the weight of the link. Negative weights are not
+ * supported, and will be ignored and treated as if they were 0.
+ *
+ * This method is inline, so it can be used to traverse the graph with suspending functions.
+ *
+ * ## Asymptotic complexity
+ * - **Time complexity**: Depends on the graph.
+ * - **Space complexity**: O(|D|), where |D| is the number of distinct successors for any given
+ *   vertex.
+ */
+public inline fun <G> G.randomWalkWeighted(
+    from: Vertex,
+    random: Random = Random,
+    action: (Vertex) -> Unit,
+) where G : SuccessorsWeight {
+  contract { callsInPlace(action) }
+
+  var current = index(from)
+  val vertices = IntVector()
+  val weights = IntVector()
+
+  while (true) {
+    action(vertex(current))
+    val size = successorsSize(current)
+    if (size == 0) return
+
+    vertices.clear()
+    weights.clear()
+
+    for (i in 0 ..< size) {
+      val weight = successorWeight(current, i)
+      if (weight <= 0) continue
+      vertices += index(successorVertex(current, i))
+      weights += weight
+    }
+
+    val total = weights.sum()
+    if (total <= 0) return // No reachable successors.
+    val value = random.nextInt(total)
+    var sum = 0
+    for (i in 0 ..< weights.size) {
+      sum += weights[i]
+      if (sum > value) {
+        current = vertices[i]
+        break
+      }
+    }
+  }
+}
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ShortestPathFasterAlgorithm.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ShortestPathFasterAlgorithm.kt
index 8d24556..986d3ac 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ShortestPathFasterAlgorithm.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/ShortestPathFasterAlgorithm.kt
@@ -14,7 +14,9 @@ import kotlin.jvm.JvmName
  * @param from the [Vertex] to start the search from.
  * @return the map of parents for each vertex in the shortest path tree from the [from] vertex.
  */
-private fun Network.shortestPathFasterAlgorithmParents(from: Vertex): VertexMap {
+private fun <N> N.shortestPathFasterAlgorithmParents(
+    from: Vertex,
+): VertexMap where N : SuccessorsWeight {
   val enqueued = BooleanArray(size)
   val distances = IntArray(size) { Int.MAX_VALUE }
   val queue = IntDequeue()
@@ -29,7 +31,7 @@ private fun Network.shortestPathFasterAlgorithmParents(from: Vertex): VertexMap
   while (queue.size > 0) {
     val v1 = vertex(queue.removeFirst())
     enqueued[index(v1)] = false
-    forEachNeighbor(v1) { v2, weight ->
+    forEachSuccessor(v1) { v2, weight ->
       val d1 = distances[index(v1)]
       val d2 = distances[index(v2)]
       if (d1 != Int.MAX_VALUE && (d2 == Int.MAX_VALUE || d1 + weight < d2)) {
@@ -62,7 +64,9 @@ private fun Network.shortestPathFasterAlgorithmParents(from: Vertex): VertexMap
  *   vertices in the network.
  * @throws NoSuchVertexException if the given [from] vertex is not in this graph.
  */
-public fun Network.shortestPathFasterAlgorithm(from: Vertex): DirectedNetwork {
+public fun <N> N.shortestPathFasterAlgorithm(
+    from: Vertex,
+): DirectedNetwork where N : SuccessorsWeight {
   if (from !in this) throw NoSuchVertexException()
   return computeNetwork(shortestPathFasterAlgorithmParents(from))
 }
@@ -84,7 +88,10 @@ public fun Network.shortestPathFasterAlgorithm(from: Vertex): DirectedNetwork {
  *   or `null` if no such path exists.
  * @throws NoSuchVertexException if the given [from] vertex or [to] vertex is not in this graph.
  */
-public fun Network.shortestPathFasterAlgorithm(from: Vertex, to: Vertex): VertexArray? {
+public fun <N> N.shortestPathFasterAlgorithm(
+    from: Vertex,
+    to: Vertex,
+): VertexArray? where N : SuccessorsWeight {
   if (from !in this) throw NoSuchVertexException()
   if (to !in this) throw NoSuchVertexException()
   return computePath(shortestPathFasterAlgorithmParents(from), from, to)
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/TopologicalSort.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/TopologicalSort.kt
index 3a45a0c..eea6242 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/TopologicalSort.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/algorithms/TopologicalSort.kt
@@ -3,9 +3,7 @@
 
 package io.github.alexandrepiveteau.graphs.algorithms
 
-import io.github.alexandrepiveteau.graphs.DirectedGraph
-import io.github.alexandrepiveteau.graphs.VertexArray
-import io.github.alexandrepiveteau.graphs.asVertexArray
+import io.github.alexandrepiveteau.graphs.*
 import io.github.alexandrepiveteau.graphs.internal.collections.IntDequeue
 import kotlin.jvm.JvmMultifileClass
 import kotlin.jvm.JvmName
@@ -23,7 +21,7 @@ import kotlin.jvm.JvmName
  * @receiver the [DirectedGraph] to sort topologically.
  * @throws IllegalArgumentException if the graph contains a cycle.
  */
-public fun DirectedGraph.topologicalSort(): VertexArray {
+public fun <G> G.topologicalSort(): VertexArray where G : Directed, G : Successors {
 
   // 0. Set up a queue of vertices to add to the topological sort, and a boolean array to keep track
   // of the vertices that have already been sorted.
@@ -50,7 +48,7 @@ public fun DirectedGraph.topologicalSort(): VertexArray {
     val vertex = queue.removeFirst()
     result.addLast(vertex)
 
-    forEachNeighbor(vertex(vertex)) {
+    forEachSuccessor(vertex(vertex)) {
       val to = index(it)
       edges[to]--
       if (edges[to] == 0 && !sorted[to]) {
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/collections/IntVector.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/collections/IntVector.kt
index 902bfc0..a21190d 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/collections/IntVector.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/collections/IntVector.kt
@@ -39,6 +39,18 @@ internal class IntVector {
     size--
   }
 
+  /** Clears the vector. */
+  fun clear() {
+    size = 0
+  }
+
+  /** Returns the sum of all the elements in the vector. */
+  fun sum(): Int {
+    var sum = 0
+    for (i in 0 until size) sum += buffer[i]
+    return sum
+  }
+
   /** Returns a copy of the vector as an [IntArray]. */
   fun toIntArray(): IntArray = buffer.copyOf(size)
 }
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyListGraph.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyListGraph.kt
index 1a019b6..739c852 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyListGraph.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyListGraph.kt
@@ -27,11 +27,15 @@ internal class AdjacencyListGraph(private val neighbors: Array<VertexArray>) : G
     return neighbors[index].size
   }
 
-  override fun successor(index: Int, neighborIndex: Int): Vertex {
+  override fun successorIndex(index: Int, neighborIndex: Int): Int {
     if (index < 0 || index >= size) throw IndexOutOfBoundsException()
     val neighbors = neighbors[index]
     if (neighborIndex < 0 || neighborIndex >= neighbors.size) throw IndexOutOfBoundsException()
-    return neighbors[neighborIndex]
+    return neighbors[neighborIndex].index
+  }
+
+  override fun successorVertex(index: Int, neighborIndex: Int): Vertex {
+    return vertex(successorIndex(index, neighborIndex))
   }
 }
 
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyListNetwork.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyListNetwork.kt
index bec4aa3..7c8510e 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyListNetwork.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyListNetwork.kt
@@ -13,14 +13,14 @@ internal class AdjacencyListNetwork(
     private val weights: Array<IntArray>,
 ) : Network, Graph by AdjacencyListGraph(neighbors) {
 
-  override fun weight(index: Int, neighborIndex: Int): Int {
+  override fun successorWeight(index: Int, neighborIndex: Int): Int {
     if (index < 0 || index >= size) throw IndexOutOfBoundsException()
     val weights = weights[index]
     if (neighborIndex < 0 || neighborIndex >= weights.size) throw IndexOutOfBoundsException()
     return weights[neighborIndex]
   }
 
-  override fun weight(index: Int, neighbor: Vertex): Int {
+  override fun successorWeight(index: Int, neighbor: Vertex): Int {
     if (index < 0 || index >= size) throw IndexOutOfBoundsException()
     val neighbors = neighbors[index]
     val neighborIndex = neighbors.binarySearch(neighbor)
diff --git a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyMatrixGraph.kt b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyMatrixGraph.kt
index c51c8aa..71ffaaa 100644
--- a/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyMatrixGraph.kt
+++ b/src/commonMain/kotlin/io/github/alexandrepiveteau/graphs/internal/graphs/AdjacencyMatrixGraph.kt
@@ -29,17 +29,21 @@ internal abstract class AdjacencyMatrixGraph(private val present: Array<BooleanA
     return present[index].count { it }
   }
 
-  override fun successor(index: Int, neighborIndex: Int): Vertex {
+  override fun successorIndex(index: Int, neighborIndex: Int): Int {
     if (index < 0 || index >= size) throw IndexOutOfBoundsException()
     val neighbors = present[index]
     var remaining = neighborIndex
     for (i in neighbors.indices) {
       if (neighbors[i]) {
-        if (remaining == 0) return Vertex(i) else remaining--
+        if (remaining == 0) return i else remaining--
       }
     }
     throw IndexOutOfBoundsException()
   }
+
+  override fun successorVertex(index: Int, neighborIndex: Int): Vertex {
+    return vertex(successorIndex(index, neighborIndex))
+  }
 }
 
 /** An implementation of [DirectedGraph] which uses an adjacency matrix to store the edges. */
diff --git a/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.complete.kt b/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.complete.kt
index 9dd3c1a..db34502 100644
--- a/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.complete.kt
+++ b/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/UndirectedGraph.complete.kt
@@ -18,7 +18,7 @@ class UndirectedEmptyGraphTests {
     assertFailsWith<IndexOutOfBoundsException> { graph.vertex(0) }
     assertFailsWith<NoSuchVertexException> { graph.index(Vertex(0)) }
     assertFailsWith<IndexOutOfBoundsException> { graph.successorsSize(0) }
-    assertFailsWith<IndexOutOfBoundsException> { graph.successor(0, 0) }
+    assertFailsWith<IndexOutOfBoundsException> { graph.successorVertex(0, 0) }
   }
 }
 
diff --git a/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/algorithms/DijkstraTests.kt b/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/algorithms/DijkstraTests.kt
index 29d758f..fa1cd30 100644
--- a/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/algorithms/DijkstraTests.kt
+++ b/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/algorithms/DijkstraTests.kt
@@ -19,9 +19,10 @@ class DijkstraTests {
 
   @Test
   fun singletonNetworkReturnsItself() {
-    val network = buildUndirectedNetwork { addVertex() }
+    var node: Vertex
+    val network = buildUndirectedNetwork { node = addVertex() }
     val expected = buildUndirectedNetwork { addVertex() }
-    val dijkstra = network.shortestPathDijkstra(network.vertex(0))
+    val dijkstra = network.shortestPathDijkstra(node)
     assertEquals(expected, dijkstra)
   }
 
diff --git a/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/builder/UndirectedNetworkBuilderTests.kt b/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/builder/UndirectedNetworkBuilderTests.kt
index 6f3bcb6..c0e442c 100644
--- a/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/builder/UndirectedNetworkBuilderTests.kt
+++ b/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/builder/UndirectedNetworkBuilderTests.kt
@@ -31,7 +31,7 @@ class UndirectedNetworkBuilderTests {
       addEdge(a edgeTo b, 2)
     }
 
-    assertEquals(3, network.weight(a, b))
+    assertEquals(3, network.successorWeight(a, b))
   }
 
   @Test
@@ -45,6 +45,6 @@ class UndirectedNetworkBuilderTests {
       addEdge(a edgeTo b, 1)
       addEdge(a edgeTo b, -2)
     }
-    assertEquals(-1, network.weight(a, b))
+    assertEquals(-1, network.successorWeight(a, b))
   }
 }
diff --git a/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/util/Assertions.kt b/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/util/Assertions.kt
index 203b2bc..7119d06 100644
--- a/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/util/Assertions.kt
+++ b/src/commonTest/kotlin/io/github/alexandrepiveteau/graphs/util/Assertions.kt
@@ -22,8 +22,8 @@ fun assertEquals(expected: Graph, actual: Graph) {
     )
     for (j in 0 until expected.successorsSize(i)) {
       assertEquals(
-          expected.successor(i, j),
-          actual.successor(i, j),
+          expected.successorVertex(i, j),
+          actual.successorVertex(i, j),
           "neighbor different: $i, $j",
       )
     }
@@ -41,7 +41,7 @@ fun assertEquals(expected: Network, actual: Network) {
   assertEqualsGraph(expected as Graph, actual as Graph)
   for (i in 0 until expected.size) {
     for (j in 0 until expected.successorsSize(i)) {
-      assertEquals(expected.weight(i, j), actual.weight(i, j))
+      assertEquals(expected.successorWeight(i, j), actual.successorWeight(i, j))
     }
   }
 }
@@ -66,8 +66,8 @@ fun assertFlowValid(
   val outgoing = IntArray(flow.size) { 0 }
   val incoming = IntArray(flow.size) { 0 }
   flow.forEachArc { (u, v) ->
-    val capacity = capacities.weight(u, v)
-    val weight = flow.weight(u, v)
+    val capacity = capacities.successorWeight(u, v)
+    val weight = flow.successorWeight(u, v)
     assertEquals(true, weight in 0..capacity)
     outgoing[u.index] += weight
     incoming[v.index] += weight