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/*
* Normaliz
* Copyright (C) 2007-2014 Winfried Bruns, Bogdan Ichim, Christof Soeger
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* As an exception, when this program is distributed through (i) the App Store
* by Apple Inc.; (ii) the Mac App Store by Apple Inc.; or (iii) Google Play
* by Google Inc., then that store may impose any digital rights management,
* device limits and/or redistribution restrictions that are required by its
* terms of service.
*/
#ifdef NMZ_MIC_OFFLOAD
#pragma offload_attribute (push, target(mic))
#endif
#include "libnormaliz/cone_helper.h"
#include <vector>
namespace libnormaliz {
using std::vector;
//---------------------------------------------------------------------------
// determines the maximal subsets in a vector of subsets given by their indicator vectors
// result returned in is_max_subset -- must be initialized outside
// only set to false in this routine
// if a set occurs more than once, only the last instance is recognized as maximal
void maximal_subsets(const vector<vector<bool> >& ind, vector<bool>& is_max_subset) {
if(ind.size()==0)
return;
size_t nr_sets=ind.size();
size_t card=ind[0].size();
vector<key_t> elem(card);
for (size_t i = 0; i <nr_sets; i++) {
if(!is_max_subset[i]) // already known to be non-maximal
continue;
size_t k=0; // counts the number of elements in set with index i
for (size_t j = 0; j <card; j++) {
if (ind[i][j]) {
elem[k]=j;
k++;
}
}
for (size_t j = 0; j <nr_sets; j++) {
if (i==j || !is_max_subset[j] ) // don't compare with itself or something known not to be maximal
continue;
size_t t;
for (t = 0; t<k; t++) {
if (!ind[j][elem[t]])
break; // not a superset
}
if (t==k) { // found a superset
is_max_subset[i]=false;
break; // the loop over j
}
}
}
}
//---------------------------------------------------------------------------
#ifdef NMZ_MIC_OFFLOAD
#pragma offload_attribute (pop)
#endif
} //end namespace libnormaliz
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