binary_heap_/erase_fn_imps.hpp
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// -*- C++ -*-
// Copyright (C) 2005-2013 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.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. 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 binary_heap_/erase_fn_imps.hpp
* Contains an implementation class for a binary_heap.
*/
PB_DS_CLASS_T_DEC
void
PB_DS_CLASS_C_DEC::
clear()
{
for (size_type i = 0; i < m_size; ++i)
erase_at(m_a_entries, i, s_no_throw_copies_ind);
__try
{
const size_type new_size = resize_policy::get_new_size_for_arbitrary(0);
entry_pointer new_entries = s_entry_allocator.allocate(new_size);
resize_policy::notify_arbitrary(new_size);
s_entry_allocator.deallocate(m_a_entries, m_actual_size);
m_actual_size = new_size;
m_a_entries = new_entries;
}
__catch(...)
{ }
m_size = 0;
PB_DS_ASSERT_VALID((*this))
}
PB_DS_CLASS_T_DEC
void
PB_DS_CLASS_C_DEC::
erase_at(entry_pointer a_entries, size_type i, false_type)
{
a_entries[i]->~value_type();
s_value_allocator.deallocate(a_entries[i], 1);
}
PB_DS_CLASS_T_DEC
void
PB_DS_CLASS_C_DEC::
erase_at(entry_pointer, size_type, true_type)
{ }
PB_DS_CLASS_T_DEC
inline void
PB_DS_CLASS_C_DEC::
pop()
{
PB_DS_ASSERT_VALID((*this))
_GLIBCXX_DEBUG_ASSERT(!empty());
pop_heap();
erase_at(m_a_entries, m_size - 1, s_no_throw_copies_ind);
resize_for_erase_if_needed();
_GLIBCXX_DEBUG_ASSERT(m_size > 0);
--m_size;
PB_DS_ASSERT_VALID((*this))
}
PB_DS_CLASS_T_DEC
template<typename Pred>
typename PB_DS_CLASS_C_DEC::size_type
PB_DS_CLASS_C_DEC::
erase_if(Pred pred)
{
PB_DS_ASSERT_VALID((*this))
typedef typename entry_pred<value_type, Pred, _Alloc, simple_value>::type
pred_t;
const size_type left = partition(pred_t(pred));
_GLIBCXX_DEBUG_ASSERT(m_size >= left);
const size_type ersd = m_size - left;
for (size_type i = left; i < m_size; ++i)
erase_at(m_a_entries, i, s_no_throw_copies_ind);
__try
{
const size_type new_size =
resize_policy::get_new_size_for_arbitrary(left);
entry_pointer new_entries = s_entry_allocator.allocate(new_size);
std::copy(m_a_entries, m_a_entries + left, new_entries);
s_entry_allocator.deallocate(m_a_entries, m_actual_size);
m_actual_size = new_size;
resize_policy::notify_arbitrary(m_actual_size);
}
__catch(...)
{ };
m_size = left;
make_heap();
PB_DS_ASSERT_VALID((*this))
return ersd;
}
PB_DS_CLASS_T_DEC
inline void
PB_DS_CLASS_C_DEC::
erase(point_iterator it)
{
PB_DS_ASSERT_VALID((*this))
_GLIBCXX_DEBUG_ASSERT(!empty());
const size_type fix_pos = it.m_p_e - m_a_entries;
std::swap(*it.m_p_e, m_a_entries[m_size - 1]);
erase_at(m_a_entries, m_size - 1, s_no_throw_copies_ind);
resize_for_erase_if_needed();
_GLIBCXX_DEBUG_ASSERT(m_size > 0);
--m_size;
_GLIBCXX_DEBUG_ASSERT(fix_pos <= m_size);
if (fix_pos != m_size)
fix(m_a_entries + fix_pos);
PB_DS_ASSERT_VALID((*this))
}
PB_DS_CLASS_T_DEC
inline void
PB_DS_CLASS_C_DEC::
resize_for_erase_if_needed()
{
if (!resize_policy::resize_needed_for_shrink(m_size))
return;
__try
{
const size_type new_size = resize_policy::get_new_size_for_shrink();
entry_pointer new_entries = s_entry_allocator.allocate(new_size);
resize_policy::notify_shrink_resize();
_GLIBCXX_DEBUG_ASSERT(m_size > 0);
std::copy(m_a_entries, m_a_entries + m_size - 1, new_entries);
s_entry_allocator.deallocate(m_a_entries, m_actual_size);
m_actual_size = new_size;
m_a_entries = new_entries;
}
__catch(...)
{ }
}
PB_DS_CLASS_T_DEC
template<typename Pred>
typename PB_DS_CLASS_C_DEC::size_type
PB_DS_CLASS_C_DEC::
partition(Pred pred)
{
size_type left = 0;
size_type right = m_size - 1;
while (right + 1 != left)
{
_GLIBCXX_DEBUG_ASSERT(left <= m_size);
if (!pred(m_a_entries[left]))
++left;
else if (pred(m_a_entries[right]))
--right;
else
{
_GLIBCXX_DEBUG_ASSERT(left < right);
std::swap(m_a_entries[left], m_a_entries[right]);
++left;
--right;
}
}
return left;
}