diff --git a/src/undirected_graph.rs b/src/undirected_graph.rs
index 14b3fa08b001ddb754676a95e6a70402244a9a01..42fc72096c9b1950af25621dd93cdac26db006a6 100644
--- a/src/undirected_graph.rs
+++ b/src/undirected_graph.rs
@@ -75,9 +75,9 @@ impl UndirectedGraph {
     fn induced_edge_permutation(
         g: &UndirectedGraph,
         h: &UndirectedGraph,
-        relabel_h_to_g: &Vec<i32>,
+        relabel_h_to_g: &[i32],
     ) -> Vec<i32> {
-        fn map_edge(relabel_h_to_g: &Vec<i32>, e: &(usize, usize)) -> (usize, usize) {
+        fn map_edge(relabel_h_to_g: &[i32], e: &(usize, usize)) -> (usize, usize) {
             let a: usize = relabel_h_to_g[e.0] as usize;
             let b: usize = relabel_h_to_g[e.1] as usize;
             return if a < b { (a, b) } else { (b, a) };