diff --git a/src/undirected_graph.rs b/src/undirected_graph.rs
index 42bebc784573ccb6c43009be2f705c2ab1594e0e..14b3fa08b001ddb754676a95e6a70402244a9a01 100644
--- a/src/undirected_graph.rs
+++ b/src/undirected_graph.rs
@@ -36,7 +36,7 @@ impl UndirectedGraph {
 
     fn degree_sequence(&self) -> Vec<usize> {
         let mut degrees = vec![0; self.num_vertices];
-        for &(a,b) in &self.edges {
+        for &(a, b) in &self.edges {
             degrees[a] += 1;
             degrees[b] += 1;
         }
@@ -53,16 +53,16 @@ impl UndirectedGraph {
         return nauty_graph;
     }
 
-    pub fn from_nauty(nauty_graph: &Vec<u64>) -> UndirectedGraph {
+    pub fn from_nauty(nauty_graph: &[u64]) -> UndirectedGraph {
         let mut graph: UndirectedGraph = UndirectedGraph {
             num_vertices: nauty_graph.len(),
             edges: vec![],
         };
-        for i in 0..nauty_graph.len() {
+        for (i, word) in nauty_graph.iter().enumerate() {
             let mut j = i + 1;
             let mut vertex_mask: u64 = 1 << ((nauty_Traces_sys::WORDSIZE as usize) - 1 - j);
             while vertex_mask != 0 {
-                if (nauty_graph[i] & vertex_mask) != 0 {
+                if (word & vertex_mask) != 0 {
                     graph.edges.push((i, j));
                 }
                 j += 1;