diff --git a/tests/test_against_anders_and_briegel.py b/tests/test_against_anders_and_briegel.py
index d74b260..e355cb8 100644
--- a/tests/test_against_anders_and_briegel.py
+++ b/tests/test_against_anders_and_briegel.py
@@ -1,5 +1,8 @@
 from abp.graphstate import GraphState
 from anders_briegel import graphsim
+import random
+import difflib
+import re
 
 def test_1():
     N=10
@@ -17,3 +20,32 @@ def test_1():
         b.act_cz(i, i+1)
 
     assert a.get_adj_list() == b.adj_list()
+
+
+def test_2():
+    N=10
+
+    a = graphsim.GraphRegister(N)
+    b = GraphState()
+
+    for i in range(N):
+        b.add_vertex(i)
+
+    for i in range(100):
+        if random.random()>0.5:
+            j = random.randint(0, N-1)
+            a.hadamard(j)
+            b.act_hadamard(j)
+        else:
+            q = random.randint(0, N-2)
+            a.cphase(q, q+1)
+            b.act_cz(q, q+1)
+
+    aa = a.get_adj_list()
+    bb = b.adj_list()
+    try:
+        assert re.sub("\\s", "", aa) == re.sub("\\s", "", bb)
+    except AssertionError:
+        print aa
+        print bb
+