Small changes in min. cost flow algorithms.
3 * This file is a part of LEMON, a generic C++ optimization library
5 * Copyright (C) 2003-2007
6 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 * (Egervary Research Group on Combinatorial Optimization, EGRES).
9 * Permission to use, modify and distribute this software is granted
10 * provided that this copyright notice appears in all copies. For
11 * precise terms see the accompanying LICENSE file.
13 * This software is provided "AS IS" with no warranty of any kind,
14 * express or implied, and with no claim as to its suitability for any
21 ///\brief Demonstrating the usage of LEMON's General Flow algorithm
23 /// This demo program reads a general network circulation problem from the
24 /// file 'circulation-input.lgf', runs the preflow based algorithm for
25 /// finding a feasible solution and writes the output
26 /// to 'circulation-input.lgf'
28 /// \include circulation_demo.cc
32 #include <lemon/list_graph.h>
33 #include <lemon/circulation.h>
34 #include <lemon/graph_reader.h>
35 #include <lemon/graph_writer.h>
37 using namespace lemon;
40 int main (int, char*[])
43 typedef ListGraph Graph;
44 typedef Graph::Node Node;
45 typedef Graph::NodeIt NodeIt;
46 typedef Graph::Edge Edge;
47 typedef Graph::EdgeIt EdgeIt;
48 typedef Graph::EdgeMap<int> EdgeMap;
49 typedef Graph::NodeMap<int> NodeMap;
50 typedef Graph::NodeMap<double> DNodeMap;
62 GraphReader<Graph>("circulation-input.lgf", g).
63 readEdgeMap("lo_cap", lo).
64 readEdgeMap("up_cap", up).
65 readNodeMap("delta", delta).
66 readEdgeMap("label", eid).
67 readNodeMap("label", nid).
68 readNodeMap("coordinates_x", cx).
69 readNodeMap("coordinates_y", cy).
72 Circulation<Graph,int> gen(g,lo,up,delta,x);
76 std::cout << "\nA feasible flow has been found.\n";
77 if(!gen.checkX(x)) std::cerr << "Oops!!!\n";
78 GraphWriter<Graph>("circulation-output.lgf", g).
79 writeEdgeMap("lo_cap", lo).
80 writeEdgeMap("up_cap", up).
81 writeEdgeMap("flow", x).
82 writeNodeMap("delta", delta).
83 writeEdgeMap("label", eid).
84 writeNodeMap("label", nid).
85 writeNodeMap("coordinates_x", cx).
86 writeNodeMap("coordinates_y", cy).
90 std::cout << "\nThere is no such a flow\n";
91 Graph::NodeMap<int> bar(g);
93 if(!gen.checkBarrier(bar)) std::cerr << "Dual Oops!!!\n";
95 GraphWriter<Graph>("circulation-output.lgf", g).
96 writeEdgeMap("lo_cap", lo).
97 writeEdgeMap("up_cap", up).
98 writeNodeMap("barrier", bar).
99 writeNodeMap("delta", delta).
100 writeEdgeMap("label", eid).
101 writeNodeMap("label", nid).
102 writeNodeMap("coordinates_x", cx).
103 writeNodeMap("coordinates_y", cy).
106 std::cout << "The output is written to file 'circulation-output.lgf'\n\n";