diff -r 741f3108a90f -r e997802b855c src/lemon/full_graph.h
--- a/src/lemon/full_graph.h	Sat Nov 13 12:24:01 2004 +0000
+++ b/src/lemon/full_graph.h	Sat Nov 13 12:53:28 2004 +0000
@@ -78,8 +78,8 @@
     ///\sa id(Edge)
     int maxId(Edge = INVALID) const { return EdgeNum-1; }
 
-    Node tail(Edge e) const { return e.id % NodeNum; }
-    Node head(Edge e) const { return e.id / NodeNum; }
+    Node source(Edge e) const { return e.id % NodeNum; }
+    Node target(Edge e) const { return e.id / NodeNum; }
 
 
     /// Node ID.
@@ -136,12 +136,12 @@
       friend class FullGraphBase;
       
     protected:
-      int id;  // NodeNum * head + tail;
+      int id;  // NodeNum * target + source;
 
       Edge(int _id) : id(_id) {}
 
-      Edge(const FullGraphBase& _graph, int tail, int head) 
-	: id(_graph.NodeNum * head+tail) {}
+      Edge(const FullGraphBase& _graph, int source, int target) 
+	: id(_graph.NodeNum * target+source) {}
     public:
       Edge() { }
       Edge (Invalid) { id = -1; }
@@ -250,14 +250,14 @@
     ///\sa id(Edge)
     int maxId(Edge = INVALID) const { return EdgeNum-1; }
 
-    Node tail(Edge e) const { 
+    Node source(Edge e) const { 
       /// \todo we may do it faster
       return ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2; 
     }
 
-    Node head(Edge e) const { 
-      int tail = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
-      return e.id - (tail) * (tail - 1) / 2; 
+    Node target(Edge e) const { 
+      int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
+      return e.id - (source) * (source - 1) / 2; 
     }
 
 
@@ -315,12 +315,12 @@
       friend class UndirFullGraphBase;
       
     protected:
-      int id;  // NodeNum * head + tail;
+      int id;  // NodeNum * target + source;
 
       Edge(int _id) : id(_id) {}
 
-      Edge(const UndirFullGraphBase& _graph, int tail, int head) 
-	: id(_graph.NodeNum * head+tail) {}
+      Edge(const UndirFullGraphBase& _graph, int source, int target) 
+	: id(_graph.NodeNum * target+source) {}
     public:
       Edge() { }
       Edge (Invalid) { id = -1; }
@@ -351,10 +351,10 @@
 
     /// \todo with specialized iterators we can make faster iterating
     void nextOut(Edge& e) const {
-      int tail = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
-      int head = e.id - (tail) * (tail - 1) / 2; 
-      ++head;
-      e.id = head < tail ? tail * (tail - 1) / 2 + head : -1;
+      int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
+      int target = e.id - (source) * (source - 1) / 2; 
+      ++target;
+      e.id = target < source ? source * (source - 1) / 2 + target : -1;
     }
 
     void firstIn(Edge& edge, const Node& node) const {
@@ -362,10 +362,10 @@
     }
     
     void nextIn(Edge& e) const {
-      int tail = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
-      int head = e.id - (tail) * (tail - 1) / 2; ++head;
-      ++tail;
-      e.id = tail < NodeNum ? tail * (tail - 1) / 2 + head : -1;
+      int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
+      int target = e.id - (source) * (source - 1) / 2; ++target;
+      ++source;
+      e.id = source < NodeNum ? source * (source - 1) / 2 + target : -1;
     }
 
   };