fix additive identity example

2 files changed, 4 insertions, 2 deletions

diff --git a/app/Web.hs b/app/Web.hs
index ba54f85..89b6ac5 100644
--- a/app/Web.hs
+++ b/app/Web.hs
@@ -97,7 +97,7 @@ examples =
   [ ("1+1=2", "one plus one equals two."),
     ("Ax.Ay.x+y=y+x", "addition is commutative."),
     ("Ex.Ay.x>y", "there exists a largest natural."),
-    ("Ee.Ax.(x+e=x & Ay.(x+y=x -> e=y))", "the additive identity exists and is unique."),
+    ("Ee.Ae'.(Ax.e'+x=x <-> e=e')", "the additive identity exists and is unique."),
     ("Ax.Ey.2y=x", "every natural is even."),
     ("Ax.Ey.(2y=x | 2y+1=x)", "every natural is either even or odd."),
     ("Ax.Ay.Az.((x=y & y=z) -> x=z)", "equality is transitive."),
diff --git a/src/Lib.hs b/src/Lib.hs
index 13dc4ac..e8bc698 100644
--- a/src/Lib.hs
+++ b/src/Lib.hs
@@ -209,6 +209,8 @@ chars n =
    in map (1 :) r ++ map (0 :) r
 
 minimize :: (Ord a) => Integer -> NFA [Int] a -> NFA [Int] a
-minimize n nfa@(NFA _ starts accepts f) = NFA states' starts accepts f
+minimize n nfa@(NFA _ starts accepts f) = NFA states' starts' accepts' f
   where
     states' = closure nfa (chars n) starts
+    starts' = starts `L.intersect` states'
+    accepts' = accepts `L.intersect` states'