diff --git a/src/models/append_graph.rs b/src/models/append_graph.rs
index 83f0127..816e6af 100644
--- a/src/models/append_graph.rs
+++ b/src/models/append_graph.rs
@@ -80,10 +80,6 @@ impl GraphTopology for AppendGraph {
         self.vertices.len()
     }
 
-    fn edge_count(&self) -> usize {
-        self.incidences.len() / 2
-    }
-
     fn vertex_capacity(&self) -> usize {
         self.vertices.len()
     }
@@ -92,6 +88,10 @@ impl GraphTopology for AppendGraph {
         VertexMap::new(default, |v| v.0, self.vertex_capacity())
     }
 
+    fn edge_count(&self) -> usize {
+        self.incidences.len() / 2
+    }
+
     fn degree(&self, v: Self::Vertex) -> usize {
         self.vertices[v.0].incidence_count
     }
diff --git a/src/models/graph.rs b/src/models/graph.rs
index d69372a..8970e24 100644
--- a/src/models/graph.rs
+++ b/src/models/graph.rs
@@ -159,10 +159,6 @@ impl GraphTopology for Graph {
         self.vertices.len()
     }
 
-    fn edge_count(&self) -> usize {
-        self.incidences.len() / 2
-    }
-
     fn vertex_capacity(&self) -> usize {
         self.vertices.capacity()
     }
@@ -171,6 +167,10 @@ impl GraphTopology for Graph {
         VertexMap::new(default, |v| v.arr_idx(), self.vertex_capacity())
     }
 
+    fn edge_count(&self) -> usize {
+        self.incidences.len() / 2
+    }
+
     fn degree(&self, v: Self::Vertex) -> usize {
         self.vertices[v].incidence_count
     }
diff --git a/src/traits.rs b/src/traits.rs
index 515c006..16c7129 100644
--- a/src/traits.rs
+++ b/src/traits.rs
@@ -9,9 +9,9 @@ pub trait GraphTopology {
     type Edge: Copy + Eq;
 
     fn vertex_count(&self) -> usize;
-    fn edge_count(&self) -> usize;
     fn vertex_capacity(&self) -> usize;
     fn vertex_map<T: Clone>(&self, default: T) -> VertexMap<Self::Vertex, T>;
+    fn edge_count(&self) -> usize;
     fn degree(&self, v: Self::Vertex) -> usize;
     fn are_adjacent(&self, v1: Self::Vertex, v2: Self::Vertex) -> bool;
     fn vertices(&self) -> impl Iterator<Item = Self::Vertex>;