diff --git a/idaplugin/rematch/collectors/flat_graph.py b/idaplugin/rematch/collectors/vectors/flat_graph.py
similarity index 86%
rename from idaplugin/rematch/collectors/flat_graph.py
rename to idaplugin/rematch/collectors/vectors/flat_graph.py
index 72579230d..b3a994250 100644
--- a/idaplugin/rematch/collectors/flat_graph.py
+++ b/idaplugin/rematch/collectors/vectors/flat_graph.py
@@ -9,9 +9,9 @@ class FlatGraphVector(Vector):
 
   def __init__(self, *args, **kwargs):
     super(FlatGraphVector, self).__init__(*args, **kwargs)
-    self.flow_chart = idaapi.FlowChart(idaapi.get_func(self.offset))
+    self.flow_chart = None
     self.visited = set()
-    self.items = list[self.flow_chart.size]
+    self.items = list()
 
   def _bb_size(self, bb):
     if bb.endEA > bb.startEA:
@@ -22,7 +22,7 @@ def _bb_size(self, bb):
 
   def _bb_value(self, bb):
     # TODO: this should be something that's uncorellated with the order of
-    #  basic blocks
+    #  basic blocks and describes basic blocks well
     return self._bb_size(bb)
 
   def _append_bbs(self, *bbs):
@@ -54,7 +54,9 @@ def _recurse_bb(self, bb):
     for sibling in siblings:
       self._recurse_siblings(sibling)
 
-  def _data(self):
+  def data(self, offset):
+    self.flow_chart = idaapi.FlowChart(idaapi.get_func(offset))
+    self.items.append(self.flow_chart.size)
     head = self._find_head()
     self._recurse_bb(head)
     return self.items