PR requested changes

Author: polgreen

src/util/graph.h

@@ -253,7 +253,7 @@ class grapht
   get_reachable(const std::vector<node_indext> &src, bool forwards) const;
 
   void disconnect_unreachable(node_indext src);
-  void disconnect_unreachable(std::vector<node_indext> src);
+  void disconnect_unreachable(const std::vector<node_indext> &src);
 
   void make_chordal();
 
@@ -475,16 +475,15 @@ void grapht<N>::visit_reachable(node_indext src)
 template <class N>
 void grapht<N>::disconnect_unreachable(node_indext src)
 {
-  std::vector<node_indext> source_nodes;
-  source_nodes.push_back(src);
+  const std::vector<node_indext> source_nodes(1, src);
   disconnect_unreachable(source_nodes);
 }
 
 /// Removes any edges between nodes in a graph that are unreachable
 /// from a vector of start nodes.
 /// \param src: vector of indices of start nodes
 template <class N>
-void grapht<N>::disconnect_unreachable(std::vector<node_indext> src)
+void grapht<N>::disconnect_unreachable(const std::vector<node_indext> &src)
 {
   std::vector<node_indext> reachable = get_reachable(src, true);
   std::sort(reachable.begin(), reachable.end());
@@ -493,7 +492,7 @@ void grapht<N>::disconnect_unreachable(std::vector<node_indext> src)
   {
     if(reachable_idx >= reachable.size())
       return;
-    PRECONDITION(i <= reachable[reachable_idx]);
+
     if(i > reachable[reachable_idx])
       throw "error disconnecting unreachable nodes";