diff -r 5a7dbeaed70e -r fa341dd6ab23 test/circulation_test.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/circulation_test.cc	Mon Dec 01 14:11:31 2008 +0000
@@ -0,0 +1,118 @@
+/* -*- mode: C++; indent-tabs-mode: nil; -*-
+ *
+ * This file is a part of LEMON, a generic C++ optimization library.
+ *
+ * Copyright (C) 2003-2008
+ * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Research Group on Combinatorial Optimization, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+///\ingroup demos
+///\file
+///\brief Demonstrating the usage of LEMON's General Flow algorithm
+///
+/// This demo program reads a general network circulation problem from the
+/// file 'circulation-input.lgf', runs the preflow based algorithm for
+/// finding a feasible solution and writes the output
+/// to 'circulation-input.lgf'
+///
+/// \include circulation_demo.cc
+
+#include <iostream>
+
+#include "test_tools.h"
+#include <lemon/list_graph.h>
+#include <lemon/circulation.h>
+#include <lemon/lgf_reader.h>
+
+using namespace lemon;
+
+char test_lgf[] =
+  "@nodes\n"
+  "label delta\n"
+  "0     0\n"
+  "1     13\n"
+  "2     0\n"
+  "3     0\n"
+  "4     0\n"
+  "5     0\n"
+  "6     0\n"
+  "7     0\n"
+  "8     -13\n"
+  "9     0\n"
+  "@edges\n"
+  "    label lo_cap up_cap\n"
+  "0 1 0     0      20\n"
+  "0 2 1     0      0\n"
+  "1 1 2     0      3\n"
+  "1 2 3     0      8\n"
+  "1 3 4     0      8\n"
+  "2 5 5     0      5\n"
+  "3 2 6     0      5\n"
+  "3 5 7     0      5\n"
+  "3 6 8     0      5\n"
+  "4 3 9     0      3\n"
+  "5 7 10    0      3\n"
+  "5 6 11    0      10\n"
+  "5 8 12    0      10\n"
+  "6 8 13    0      8\n"
+  "8 9 14    0      20\n"
+  "8 1 15    0      5\n"
+  "9 5 16    0      5\n"
+  "@attributes\n"
+  "source 1\n"
+  "sink   8\n";
+
+int main (int, char*[])
+{
+
+    typedef ListDigraph Digraph;
+    typedef Digraph::Node Node;
+    typedef Digraph::NodeIt NodeIt;
+    typedef Digraph::Arc Arc;
+    typedef Digraph::ArcIt ArcIt;
+    typedef Digraph::ArcMap<int> ArcMap;
+    typedef Digraph::NodeMap<int> NodeMap;
+    typedef Digraph::NodeMap<double> DNodeMap;
+
+    Digraph g;
+    ArcMap lo(g);
+    ArcMap up(g);
+    NodeMap delta(g);
+    NodeMap nid(g);
+    ArcMap eid(g);
+    Node source, sink;
+    
+    std::istringstream input(test_lgf);
+    DigraphReader<Digraph>(g,input).
+      arcMap("lo_cap", lo).
+      arcMap("up_cap", up).
+      nodeMap("delta", delta).
+      arcMap("label", eid).
+      nodeMap("label", nid).
+      node("source",source).
+      node("sink",sink).
+      run();
+
+    Circulation<Digraph> gen(g,lo,up,delta);
+    bool ret=gen.run();
+    check(ret,"A feasible solution should have been found.");
+    check(gen.checkFlow(), "The found flow is corrupt.");
+    
+    delta[source]=14;
+    delta[sink]=-14;
+    
+    bool ret2=gen.run();
+    check(!ret2,"A feasible solution should not have been found.");
+    check(gen.checkBarrier(), "The found barrier is corrupt.");
+
+}