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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
* Main authors:
* Christian Schulte <schulte@gecode.org>
*
* Copyright:
* Christian Schulte, 2002
*
* This file is part of Gecode, the generic constraint
* development environment:
* http://www.gecode.org
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include <gecode/driver.hh>
#include <gecode/int.hh>
#include <gecode/minimodel.hh>
using namespace Gecode;
/**
* \name %Graph specification for independent sets
*
* \relates IndSet
*/
//@{
/// %Graph specification
class Graph {
public:
const int n_v; ///< Number of vertices
const int n_e; ///< Number of edges
const int* e; ///< Arrays of edges (as vertex pairs)
Graph(const int n_v0, const int n_e0, const int* e0)
: n_v(n_v0), n_e(n_e0), e(e0) {}
};
const int e_20_10[] = {
0, 4, 2,12, 12,14, 18,19, 7,10,
9,12, 5,11, 6,15, 3,18, 7,16
};
const Graph g_20_10(20,10,e_20_10);
const int e_40_20[] = {
21,30, 11,30, 19,38, 20,25, 11,24,
20,33, 8,39, 4, 5, 6,16, 5,32,
0, 9, 5,24, 25,28, 36,38, 14,20,
19,25, 11,22, 13,30, 7,36, 15,33
};
const Graph g_40_20(40, 20, e_40_20);
//@}
/**
* \brief %Example: Independent sets in a graph
*
* \ingroup Example
*
*/
class IndSet : public IntMaximizeScript {
protected:
/// %Graph used
const Graph& g;
/// Whether vertex included in independent set
BoolVarArray v;
/// How many elements has indipendent set
IntVar k;
public:
/// Actual model
IndSet(const SizeOptions& opt)
: IntMaximizeScript(opt),
g(opt.size() == 0 ? g_20_10 : g_40_20),
v(*this,g.n_v,0,1), k(*this,0,g.n_v) {
const int* e = g.e;
for (int i = g.n_e; i--; ) {
const int* e1 = e++; const int* e2 = e++;
rel(*this, v[*e1], BOT_AND, v[*e2], 0);
}
linear(*this, v, IRT_EQ, k);
branch(*this, v, BOOL_VAR_NONE(), BOOL_VAL_MIN());
}
/// Constructor for cloning \a s
IndSet(IndSet& s) : IntMaximizeScript(s), g(s.g) {
v.update(*this, s.v);
k.update(*this, s.k);
}
/// Copy during cloning
virtual Space*
copy(void) {
return new IndSet(*this);
}
/// Print solution
virtual void
print(std::ostream& os) const {
os << "\tk = " << k << std::endl
<< "\tv[] = " << v << std::endl;
}
/// Return solution cost
virtual IntVar cost(void) const {
return k;
}
};
/** \brief Main-function
* \relates IndSet
*/
int
main(int argc, char* argv[]) {
SizeOptions opt("IndSet");
opt.solutions(0);
opt.size(1);
opt.iterations(2000);
opt.parse(argc,argv);
IntMaximizeScript::run<IndSet,BAB,SizeOptions>(opt);
return 0;
}
// STATISTICS: example-any