diff --git a/.gitignore b/.gitignore
index 8cfad81..0be40d4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+*.pdf
 # Project-specific
 ab/
 anders_briegel
diff --git a/abp.py b/abp.py
deleted file mode 100644
index 9dafe9b..0000000
--- a/abp.py
+++ /dev/null
@@ -1 +0,0 @@
-nothing
diff --git a/graph.py b/graph.py
new file mode 100644
index 0000000..735ee05
--- /dev/null
+++ b/graph.py
@@ -0,0 +1,48 @@
+import networkx as nx
+from matplotlib import pyplot as plt
+from vops import *
+
+class Graph(object):
+
+    def __init__(self, n):
+        self.vertices = [set() for i in xrange(n)]
+        self.vops = [hadamard for i in xrange(n)]
+
+    def add_edge(self, v1, v2):
+        self.vertices[v1].add(v2)
+        self.vertices[v2].add(v1)
+
+    def del_edge(self, v1, v2):
+        self.vertices[v1].remove(v2)
+        self.vertices[v2].remove(v1)
+
+    def edgelist(self):
+        edges = frozenset(frozenset((i, n))
+                for i, v in enumerate(self.vertices)
+                for n in v)
+        return [tuple(e) for e in edges]
+
+    def draw(self, filename="out.pdf"):
+        g = nx.from_edgelist(self.edgelist())
+        pos = nx.spring_layout(g)
+        nx.draw_networkx_nodes(g, pos, node_color="white", node_size=1000)
+        nx.draw_networkx_labels(g, pos)
+        nx.draw_networkx_edges(g, pos)
+        for i, vop in enumerate(self.vops):
+            if not i in pos: continue
+            x, y = pos[i]
+            plt.text(x, y+0.1, vops[vop], ha="center")
+
+        plt.axis('off')
+        plt.savefig(filename)
+
+if __name__ == '__main__':
+    g = Graph(10)
+    g.add_edge(0, 1)
+    g.add_edge(1, 3)
+    g.add_edge(3, 2)
+    g.add_edge(3, 0)
+    g.add_edge(2, 0)
+    print g.edgelist()
+
+    g.draw()
diff --git a/tests/test_graph.py b/tests/test_graph.py
new file mode 100644
index 0000000..b9d339b
--- /dev/null
+++ b/tests/test_graph.py
@@ -0,0 +1,15 @@
+from graph import Graph
+
+def test_graph():
+    g = Graph(3)
+    g.add_edge(0,1)
+    g.add_edge(1,2)
+    g.add_edge(2,0)
+    assert g.vertices[0]==set([1,2])
+
+    g.del_edge(0,1)
+    assert g.vertices[0]==set([2])
+    el = g.edgelist()
+    assert (1,2) in el
+    assert not (0,1) in el
+    assert len(el)==2
diff --git a/vops.py b/vops.py
new file mode 100644
index 0000000..8827c37
--- /dev/null
+++ b/vops.py
@@ -0,0 +1,3 @@
+vops = ["hadamard"]
+globals().update({x:i for i, x in enumerate(vops)})
+