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// -*- C++ -*-
// Copyright (C) 2005-2023 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library 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, or (at your option) any later
// version.
// This library 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 library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
// Permission to use, copy, modify, sell, and distribute this software
// is hereby granted without fee, provided that the above copyright
// notice appears in all copies, and that both that copyright notice
// and this permission notice appear in supporting documentation. None
// of the above authors, nor IBM Haifa Research Laboratories, make any
// representation about the suitability of this software for any
// purpose. It is provided "as is" without express or implied
// warranty.
/**
* @file string_ranged_hash_fn.hpp
* Contains a ranged string hash function.
*/
#ifndef PB_DS_STRING_RANGED_HASH_FN_HPP
#define PB_DS_STRING_RANGED_HASH_FN_HPP
#include <string>
#include <hash_fn/dna_str_limit.hpp>
namespace __gnu_pbds
{
namespace test
{
template<typename Comb_Fn>
class string_ranged_hash_fn : public Comb_Fn
{
private:
size_t _M_limit;
public:
typedef Comb_Fn comb_fn;
typedef detail::comb_hash_fn_string_form<comb_fn> string_form;
inline size_t
operator()(const std::string& r_str) const
{
size_t ret = 0;
std::string::const_iterator b = r_str.begin();
std::string::const_iterator e = r_str.end();
size_t i = 0;
while (i < _M_limit&& b != e)
{
ret *= 5;
ret += static_cast<size_t>(*(b++));
++i;
}
return (comb_fn::operator()(ret));
}
void
swap(string_ranged_hash_fn<Comb_Fn>& other)
{
std::swap(_M_limit, other._M_limit);
comb_fn::swap(other);
}
void
notify_resized(size_t new_size)
{
comb_fn::notify_resized(new_size);
_M_limit = dna_str_limit(new_size);
}
static std::string
name()
{ return ("string_ranged_hash_fn_" + string_form<comb_fn>::name()); }
static std::string
desc()
{ return ("string ranged-hash using" + string_form<comb_fn>::desc()); }
};
} // namespace test
} // namespace __gnu_pbds
#endif
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