Changeset 591:493533ead9df in lemon-main

Timestamp:

04/15/09 11:41:25 (16 years ago)

Author:

Peter Kovacs <kpeter@…>

Branch:

default

Phase:

public

Message:

Bug fix in the Euler iterators (#264)
Handle the case when the first node is isolated.

File:

• lemon/euler.h (modified) (2 diffs)

lemon/euler.h

@@ -79 +79 @@
       : g(gr), nedge(g)
     {
-      if(start==INVALID) start=NodeIt(g);
-      for(NodeIt n(g);n!=INVALID;++n) nedge[n]=OutArcIt(g,n);
-      while(nedge[start]!=INVALID) {
-        euler.push_back(nedge[start]);
-        Node next=g.target(nedge[start]);
-        ++nedge[start];
-        start=next;
+      if (start==INVALID) {
+        NodeIt n(g);
+        while (n!=INVALID && OutArcIt(g,n)==INVALID) ++n;
+        start=n;
+      }
+      if (start!=INVALID) {
+        for (NodeIt n(g); n!=INVALID; ++n) nedge[n]=OutArcIt(g,n);
+        while (nedge[start]!=INVALID) {
+          euler.push_back(nedge[start]);
+          Node next=g.target(nedge[start]);
+          ++nedge[start];
+          start=next;
+        }
       }
     }
@@ -172 +178 @@
       : g(gr), nedge(g), visited(g, false)
     {
-      if(start==INVALID) start=NodeIt(g);
-      for(NodeIt n(g);n!=INVALID;++n) nedge[n]=OutArcIt(g,n);
-      while(nedge[start]!=INVALID) {
-        euler.push_back(nedge[start]);
-        visited[nedge[start]]=true;
-        Node next=g.target(nedge[start]);
-        ++nedge[start];
-        start=next;
-        while(nedge[start]!=INVALID && visited[nedge[start]]) ++nedge[start];
+      if (start==INVALID) {
+        NodeIt n(g);
+        while (n!=INVALID && OutArcIt(g,n)==INVALID) ++n;
+        start=n;
+      }
+      if (start!=INVALID) {
+        for (NodeIt n(g); n!=INVALID; ++n) nedge[n]=OutArcIt(g,n);
+        while(nedge[start]!=INVALID) {
+          euler.push_back(nedge[start]);
+          visited[nedge[start]]=true;
+          Node next=g.target(nedge[start]);
+          ++nedge[start];
+          start=next;
+          while(nedge[start]!=INVALID && visited[nedge[start]]) ++nedge[start];
+        }
       }
     }