1 files changed, 9 insertions, 12 deletions
diff --git a/src/parse/regex/enfa.rs b/src/parse/regex/enfa.rs
index fea2976..b0588ab 100644
--- a/src/parse/regex/enfa.rs
+++ b/src/parse/regex/enfa.rs
@@ -233,13 +233,12 @@ impl Thread {
             .into_iter()
             .map(|t| t.step(enfa, input))
             .collect();
-        let negatives = self
+        let negatives: Vec<_> = self
             .negatives
             .into_iter()
-            .map(|t| t.step(enfa, input))
+            .flat_map(|t| t.step(enfa, input))
             .collect();
         let positives = cartesian_product(positives);
-        let negatives = cartesian_product(negatives);
         let next_states: Vec<StateId> = enfa.states[self.state]
             .trans
             .iter()
@@ -258,15 +257,13 @@ impl Thread {
 
         for s in next_states {
             for p in positives.clone() {
-                for n in negatives.clone() {
-                    if let Some(thread) = Self::new(enfa, s, p.clone(), n) {
-                        thread.step_epsilon0(
-                            enfa,
-                            ret,
-                            &mut vec![false; enfa.states.len()],
-                            Vec::new(),
-                        );
-                    }
+                if let Some(thread) = Self::new(enfa, s, p.clone(), negatives.clone()) {
+                    thread.step_epsilon0(
+                        enfa,
+                        ret,
+                        &mut vec![false; enfa.states.len()],
+                        Vec::new(),
+                    );
                 }
             }
         }