permlib  0.2.6
Library for permutation computations
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include/permlib/construct/known_bsgs_construction.h
00001 // ---------------------------------------------------------------------------
00002 //
00003 //  This file is part of PermLib.
00004 //
00005 // Copyright (c) 2009-2011 Thomas Rehn <thomas@carmen76.de>
00006 // All rights reserved.
00007 // 
00008 // Redistribution and use in source and binary forms, with or without
00009 // modification, are permitted provided that the following conditions
00010 // are met:
00011 // 1. Redistributions of source code must retain the above copyright
00012 //    notice, this list of conditions and the following disclaimer.
00013 // 2. Redistributions in binary form must reproduce the above copyright
00014 //    notice, this list of conditions and the following disclaimer in the
00015 //    documentation and/or other materials provided with the distribution.
00016 // 3. The name of the author may not be used to endorse or promote products
00017 //    derived from this software without specific prior written permission.
00018 // 
00019 // THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
00020 // IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
00021 // OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
00022 // IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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00029 //
00030 // ---------------------------------------------------------------------------
00031 
00032 
00033 #ifndef KNOWNBSGSCONSTRUCTION_H_
00034 #define KNOWNBSGSCONSTRUCTION_H_
00035 
00036 #include <permlib/construct/base_construction.h>
00037 #include <permlib/bsgs.h>
00038 
00039 namespace permlib {
00040 
00042 template <class PERM, class TRANS>
00043 class KnownBSGSConstruction : public BaseConstruction<PERM, TRANS> {
00044 public:
00046 
00049         KnownBSGSConstruction(unsigned int n);
00050 
00052 
00058         template <class ForwardIterator, class InputIterator>
00059         BSGS<PERM, TRANS> construct(ForwardIterator generatorsBegin, ForwardIterator generatorsEnd, InputIterator knownBaseBegin, InputIterator knownBaseEnd) const;
00060 };
00061 
00062 //
00063 //     ----       IMPLEMENTATION
00064 //
00065 
00066 template <class PERM, class TRANS>
00067 KnownBSGSConstruction<PERM,TRANS>::KnownBSGSConstruction(unsigned int n) 
00068         : BaseConstruction<PERM, TRANS>(n)
00069 { }
00070 
00071 
00072 template <class PERM, class TRANS>
00073 template <class ForwardIterator, class InputIterator>
00074 BSGS<PERM, TRANS> KnownBSGSConstruction<PERM, TRANS>
00075 	::construct(ForwardIterator generatorsBegin, ForwardIterator generatorsEnd, InputIterator knownBaseBegin, InputIterator knownBaseEnd) const
00076 {
00077         const unsigned int &n = this->m_n;
00078         BSGS<PERM, TRANS> ret(n);
00079         std::vector<std::list<typename PERM::ptr> > S;
00080         this->setup(generatorsBegin, generatorsEnd, knownBaseBegin, knownBaseEnd, ret, S);
00081         BOOST_ASSERT( S.size() > 0 );
00082         // the strong generating set of the group is the
00083         // stabilizer of the empty set of the given generators
00084         ret.S.insert(ret.S.end(), S[0].begin(), S[0].end());
00085         return ret;
00086 }
00087 
00088 }
00089 
00090 #endif // -- KNOWNBSGSCONSTRUCTION_H_