# HG changeset patch
# User Peter Kovacs <kpeter@inf.elte.hu>
# Date 1224763613 -7200
# Node ID 29baa4a189bffe0b76d94fca01b80b08e3d64a8e
# Parent  89f6fff82e933b518612eccdd2e24ef55c1da0aa
Port demo/hello_lemon.cc from SVN -r3501

diff -r 89f6fff82e93 -r 29baa4a189bf demo/hello_lemon.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/demo/hello_lemon.cc	Thu Oct 23 14:06:53 2008 +0200
@@ -0,0 +1,96 @@
+/* -*- 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.
+ *
+ */
+
+///\file
+///\brief Demonstrating the basic concepts and fetures of LEMON
+///
+/// This program is intended to be a "Hello World!" program that shows
+/// the very basic notions of LEMON: \ref graphs "graphs" and
+/// \ref maps "maps".
+///
+/// \include hello_lemon.cc
+
+#include <iostream>
+#include <lemon/list_graph.h>
+
+int main()
+{
+  // Convenience type definitions
+  typedef lemon::ListDigraph Digraph;
+  typedef Digraph::Node Node;
+  typedef Digraph::Arc Arc;
+  typedef Digraph::NodeIt NodeIt;
+  typedef Digraph::ArcIt ArcIt;
+  typedef Digraph::ArcMap<int> LengthMap;
+  using lemon::INVALID;
+
+  // Create a directed graph
+  Digraph g;
+
+  // Add nodes to the digraph
+  Node v1 = g.addNode();
+  Node v2 = g.addNode();
+  Node v3 = g.addNode();
+  Node v4 = g.addNode();
+
+  // Add arcs to the digraph
+  Arc v1_v2 = g.addArc(v1, v2);
+  Arc v1_v3 = g.addArc(v1, v3);
+  Arc v2_v3 = g.addArc(v2, v3);
+  Arc v2_v4 = g.addArc(v2, v4);
+  Arc v3_v4 = g.addArc(v3, v4);
+
+  // Create an arc map (length)
+  LengthMap length(g);
+
+  // Set the length of each arc
+  length[v1_v2]  = 10;
+  length[v1_v3]  = 20;
+  length[v2_v3] = 5;
+  length[v2_v4] = 25;
+  length[v3_v4] = 10;
+
+  // Welcome message
+  std::cout << "Hello World!" << std::endl;
+  std::cout << "This is LEMON library here. We have a direceted graph.";
+  std::cout << std::endl << std::endl;
+
+  // Iterate through the nodes and print their IDs
+  std::cout << "Nodes:";
+  for (NodeIt n(g); n != INVALID; ++n)
+    std::cout << " " << g.id(n);
+  std::cout << std::endl;
+
+  // Iterate through the arcs and print the IDs of their
+  // source and target nodes
+  std::cout << "Arcs:";
+  for (ArcIt a(g); a != INVALID; ++a)
+    std::cout << " (" << g.id(g.source(a)) << ","
+              << g.id(g.target(a)) << ")";
+  std::cout << std::endl << std::endl;
+
+  // Iterate through the arcs and print their length
+  std::cout << "There is a map on the arcs (length):" << std::endl;
+  std::cout << std::endl;
+  for (ArcIt a(g); a != INVALID; ++a)
+    std::cout << "length(" << g.id(g.source(a)) << ","
+              << g.id(g.target(a)) << ")=" << length[a] << std::endl;
+  std::cout << std::endl;
+
+  return 0;
+}