diff --git a/src/generators.rs b/src/generators.rs
index 2c7a94c..1456741 100644
--- a/src/generators.rs
+++ b/src/generators.rs
@@ -60,10 +60,11 @@ where
 ///
 /// [Path graph]: https://en.wikipedia.org/wiki/Path_graph
 pub fn path<G: GraphTopologyAddition>(graph: &mut G, n: usize) -> (Vec<G::Vertex>, Vec<G::Edge>) {
+    let edge_capacity = n.saturating_sub(1);
     graph.reserve_vertices(n);
-    graph.reserve_edges(n - 1);
+    graph.reserve_edges(edge_capacity);
     let vertices: Vec<_> = (0..n).map(|_| graph.add_vertex()).collect();
-    let edges = (0..n - 1)
+    let edges = (0..edge_capacity)
         .map(|i| graph.add_edge(vertices[i], vertices[i + 1]))
         .collect();
     (vertices, edges)
@@ -97,12 +98,15 @@ pub fn cycle<G: GraphTopologyAddition>(graph: &mut G, n: usize) -> (Vec<G::Verte
 /// For `n == 0`, nothing is added. For `n == 1`, only a single vertex is added.
 ///
 /// [Complete graph]: https://en.wikipedia.org/wiki/Complete_graph
-pub fn complete<G: GraphTopologyAddition>(graph: &mut G, n: usize) -> (Vec<G::Vertex>, Vec<G::Edge>) {
-    let capacity = n * (n - 1) / 2;
+pub fn complete<G: GraphTopologyAddition>(
+    graph: &mut G,
+    n: usize,
+) -> (Vec<G::Vertex>, Vec<G::Edge>) {
+    let edge_capacity = n * n.saturating_sub(1) / 2;
     graph.reserve_vertices(n);
-    graph.reserve_edges(capacity);
+    graph.reserve_edges(edge_capacity);
     let vertices: Vec<_> = (0..n).map(|_| graph.add_vertex()).collect();
-    let mut edges = Vec::with_capacity(capacity);
+    let mut edges = Vec::with_capacity(edge_capacity);
     for (i, &u) in vertices.iter().enumerate() {
         for &v in &vertices[i + 1..] {
             edges.push(graph.add_edge(u, v));