# HG changeset patch
# User beckerjc
# Date 1082238648 0
# Node ID 4b89077ab715d8e9ce87af7675de25bf1f229462
# Parent  01fb9da7a3633fd75b9bf8bedb94488724e82fb5
A successful work-around for using const map reference as an output
parameter to Kruskal().

diff -r 01fb9da7a363 -r 4b89077ab715 src/work/johanna/kruskal.h
--- a/src/work/johanna/kruskal.h	Sat Apr 17 19:54:04 2004 +0000
+++ b/src/work/johanna/kruskal.h	Sat Apr 17 21:50:48 2004 +0000
@@ -37,6 +37,29 @@
     return tot_cost;
   }
 
+  /* A work-around for running Kruskal with const-reference bool maps... */
+
+  template<typename Map>
+  class NonConstMapWr {
+    const Map &m;
+  public:
+    typedef typename Map::ValueType ValueType;
+
+    NonConstMapWr(const Map &_m) : m(_m) {}
+
+    template<typename KeyType>
+    void set(KeyType const& k, ValueType const &v) const { m.set(k,v); }
+  };
+
+  template <typename Graph, typename InputEdgeOrder, typename OutBoolMap>
+  inline
+  typename InputEdgeOrder::ValueType
+  Kruskal(Graph const& G, InputEdgeOrder const& edges, 
+	  OutBoolMap const& out_map)
+  {
+    NonConstMapWr<OutBoolMap> map_wr(out_map);
+    return Kruskal(G, edges, map_wr);
+  }  
 
   
   /* ** ** Output-objektumok: egyszeruen extra bool mapek ** ** */
@@ -49,7 +72,7 @@
 
   template<typename Iterator>
   class SequenceOutput {
-    Iterator it;
+    mutable Iterator it;
 
   public:
     typedef bool ValueType;
@@ -57,7 +80,7 @@
     SequenceOutput(Iterator const &_it) : it(_it) {}
 
     template<typename KeyType>
-    void set(KeyType const& k, bool v) { if(v) {*it=k; ++it;} }
+    void set(KeyType const& k, bool v) const { if(v) {*it=k; ++it;} }
   };
 
   template<typename Iterator>
@@ -177,6 +200,7 @@
   /// \brief Wrapper to Kruskal().
   /// Input is from an EdgeMap, output is a plain boolmap.
   template <typename Graph, typename EdgeCostMap, typename RetEdgeBoolMap>
+  inline
   typename EdgeCostMap::ValueType
   Kruskal_EdgeCostMapIn_BoolMapOut(Graph const& G,
 				   EdgeCostMap const& edge_costs,
@@ -193,6 +217,7 @@
   /// \brief Wrapper to Kruskal().
   /// Input is from an EdgeMap, output is to a sequence.
   template <typename Graph, typename EdgeCostMap, typename RetIterator>
+  inline
   typename EdgeCostMap::ValueType
   Kruskal_EdgeCostMapIn_IteratorOut(Graph const& G,
 				    EdgeCostMap const& edge_costs,
diff -r 01fb9da7a363 -r 4b89077ab715 src/work/johanna/kruskal_test.cc
--- a/src/work/johanna/kruskal_test.cc	Sat Apr 17 19:54:04 2004 +0000
+++ b/src/work/johanna/kruskal_test.cc	Sat Apr 17 21:50:48 2004 +0000
@@ -100,12 +100,18 @@
   }
 
   tree_edge_vec.clear();
-  SequenceOutput< back_insert_iterator< vector<Edge> > > 
-    vec_filler(back_inserter(tree_edge_vec));
+//   SequenceOutput< back_insert_iterator< vector<Edge> > > 
+//     vec_filler(back_inserter(tree_edge_vec));
+//   cout << "Nemkonst koltseggel tarhatekonyabban: "
+//        << Kruskal(G,
+// 		  KruskalMapVec<ECostMap>(G, edge_cost_map),
+// 		  vec_filler)
+//        << endl;
   cout << "Nemkonst koltseggel tarhatekonyabban: "
        << Kruskal(G,
 		  KruskalMapVec<ECostMap>(G, edge_cost_map),
-		  vec_filler)
+		  makeSequenceOutput(back_inserter(tree_edge_vec))
+		  )
        << endl;
 
   i = 1;