mingw/lib/gcc/mingw32/4.3.3/include/c++/ext/pb_ds/detail/eq_fn/eq_by_less.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005, 2006 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the terms
   7 // of the GNU General Public License as published by the Free Software
   8 // Foundation; either version 2, or (at your option) any later
   9 // version.
  10
  11 // This library is distributed in the hope that it will be useful, but
  12 // WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 // General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License
  17 // along with this library; see the file COPYING.  If not, write to
  18 // the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
  19 // MA 02111-1307, USA.
  20
  21 // As a special exception, you may use this file as part of a free
  22 // software library without restriction.  Specifically, if other files
  23 // instantiate templates or use macros or inline functions from this
  24 // file, or you compile this file and link it with other files to
  25 // produce an executable, this file does not by itself cause the
  26 // resulting executable to be covered by the GNU General Public
  27 // License.  This exception does not however invalidate any other
  28 // reasons why the executable file might be covered by the GNU General
  29 // Public License.
  30
  31 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
  32
  33 // Permission to use, copy, modify, sell, and distribute this software
  34 // is hereby granted without fee, provided that the above copyright
  35 // notice appears in all copies, and that both that copyright notice
  36 // and this permission notice appear in supporting documentation. None
  37 // of the above authors, nor IBM Haifa Research Laboratories, make any
  38 // representation about the suitability of this software for any
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  40 // warranty.
  41
  42 /**
  43  * @file eq_by_less.hpp
  44  * Contains an equivalence function.
  45  */
  46
  47 #ifndef PB_DS_EQ_BY_LESS_HPP
  48 #define PB_DS_EQ_BY_LESS_HPP
  49
  50 #include <utility>
  51 #include <functional>
  52 #include <vector>
  53 #include <assert.h>
  54 #include <ext/pb_ds/detail/types_traits.hpp>
  55
  56 namespace __gnu_pbds
  57 {
  58   namespace detail
  59   {
  60     template<typename Key, class Cmp_Fn>
  61     struct eq_by_less : private Cmp_Fn
  62     {
  63       bool
  64       operator()(const Key& r_lhs, const Key& r_rhs) const
  65       {
  66         const bool l = Cmp_Fn::operator()(r_lhs, r_rhs);
  67         const bool g = Cmp_Fn::operator()(r_rhs, r_lhs);
  68         return !(l || g);
  69       }
  70     };
  71   } // namespace detail
  72 } // namespace __gnu_pbds
  73
  74 #endif // #ifndef PB_DS_EQ_BY_LESS_HPP