rb_tree_map_/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 rb_tree_map_/erase_fn_imps.hpp
* Contains an implementation for rb_tree_.
*/
PB_DS_CLASS_T_DEC
inline bool
PB_DS_CLASS_C_DEC::
erase(key_const_reference r_key)
{
point_iterator it = this->find(r_key);
if (it == base_type::end())
return false;
erase(it);
return true;
}
PB_DS_CLASS_T_DEC
inline typename PB_DS_CLASS_C_DEC::iterator
PB_DS_CLASS_C_DEC::
erase(iterator it)
{
PB_DS_ASSERT_VALID((*this))
if (it == base_type::end())
return it;
iterator ret_it = it;
++ret_it;
erase_node(it.m_p_nd);
PB_DS_ASSERT_VALID((*this))
return ret_it;
}
PB_DS_CLASS_T_DEC
inline typename PB_DS_CLASS_C_DEC::reverse_iterator
PB_DS_CLASS_C_DEC::
erase(reverse_iterator it)
{
PB_DS_ASSERT_VALID((*this))
if (it.m_p_nd == base_type::m_p_head)
return it;
reverse_iterator ret_it = it;
++ret_it;
erase_node(it.m_p_nd);
PB_DS_ASSERT_VALID((*this))
return ret_it;
}
PB_DS_CLASS_T_DEC
template<typename Pred>
inline typename PB_DS_CLASS_C_DEC::size_type
PB_DS_CLASS_C_DEC::
erase_if(Pred pred)
{
PB_DS_ASSERT_VALID((*this))
size_type num_ersd = 0;
iterator it = base_type::begin();
while (it != base_type::end())
{
if (pred(*it))
{
++num_ersd;
it = erase(it);
}
else
++it;
}
PB_DS_ASSERT_VALID((*this))
return num_ersd;
}
PB_DS_CLASS_T_DEC
void
PB_DS_CLASS_C_DEC::
erase_node(node_pointer p_nd)
{
remove_node(p_nd);
base_type::actual_erase_node(p_nd);
PB_DS_ASSERT_VALID((*this))
}
PB_DS_CLASS_T_DEC
void
PB_DS_CLASS_C_DEC::
remove_node(node_pointer p_z)
{
this->update_min_max_for_erased_node(p_z);
node_pointer p_y = p_z;
node_pointer p_x = 0;
node_pointer p_new_x_parent = 0;
if (p_y->m_p_left == 0)
p_x = p_y->m_p_right;
else if (p_y->m_p_right == 0)
p_x = p_y->m_p_left;
else
{
p_y = p_y->m_p_right;
while (p_y->m_p_left != 0)
p_y = p_y->m_p_left;
p_x = p_y->m_p_right;
}
if (p_y == p_z)
{
p_new_x_parent = p_y->m_p_parent;
if (p_x != 0)
p_x->m_p_parent = p_y->m_p_parent;
if (base_type::m_p_head->m_p_parent == p_z)
base_type::m_p_head->m_p_parent = p_x;
else if (p_z->m_p_parent->m_p_left == p_z)
{
p_y->m_p_left = p_z->m_p_parent;
p_z->m_p_parent->m_p_left = p_x;
}
else
{
p_y->m_p_left = 0;
p_z->m_p_parent->m_p_right = p_x;
}
}
else
{
p_z->m_p_left->m_p_parent = p_y;
p_y->m_p_left = p_z->m_p_left;
if (p_y != p_z->m_p_right)
{
p_new_x_parent = p_y->m_p_parent;
if (p_x != 0)
p_x->m_p_parent = p_y->m_p_parent;
p_y->m_p_parent->m_p_left = p_x;
p_y->m_p_right = p_z->m_p_right;
p_z->m_p_right->m_p_parent = p_y;
}
else
p_new_x_parent = p_y;
if (base_type::m_p_head->m_p_parent == p_z)
base_type::m_p_head->m_p_parent = p_y;
else if (p_z->m_p_parent->m_p_left == p_z)
p_z->m_p_parent->m_p_left = p_y;
else
p_z->m_p_parent->m_p_right = p_y;
p_y->m_p_parent = p_z->m_p_parent;
std::swap(p_y->m_red, p_z->m_red);
p_y = p_z;
}
this->update_to_top(p_new_x_parent, (node_update* )this);
if (p_y->m_red)
return;
remove_fixup(p_x, p_new_x_parent);
}
PB_DS_CLASS_T_DEC
void
PB_DS_CLASS_C_DEC::
remove_fixup(node_pointer p_x, node_pointer p_new_x_parent)
{
_GLIBCXX_DEBUG_ASSERT(p_x == 0 || p_x->m_p_parent == p_new_x_parent);
while (p_x != base_type::m_p_head->m_p_parent && is_effectively_black(p_x))
if (p_x == p_new_x_parent->m_p_left)
{
node_pointer p_w = p_new_x_parent->m_p_right;
if (p_w->m_red)
{
p_w->m_red = false;
p_new_x_parent->m_red = true;
base_type::rotate_left(p_new_x_parent);
p_w = p_new_x_parent->m_p_right;
}
if (is_effectively_black(p_w->m_p_left)
&& is_effectively_black(p_w->m_p_right))
{
p_w->m_red = true;
p_x = p_new_x_parent;
p_new_x_parent = p_new_x_parent->m_p_parent;
}
else
{
if (is_effectively_black(p_w->m_p_right))
{
if (p_w->m_p_left != 0)
p_w->m_p_left->m_red = false;
p_w->m_red = true;
base_type::rotate_right(p_w);
p_w = p_new_x_parent->m_p_right;
}
p_w->m_red = p_new_x_parent->m_red;
p_new_x_parent->m_red = false;
if (p_w->m_p_right != 0)
p_w->m_p_right->m_red = false;
base_type::rotate_left(p_new_x_parent);
this->update_to_top(p_new_x_parent, (node_update* )this);
break;
}
}
else
{
node_pointer p_w = p_new_x_parent->m_p_left;
if (p_w->m_red == true)
{
p_w->m_red = false;
p_new_x_parent->m_red = true;
base_type::rotate_right(p_new_x_parent);
p_w = p_new_x_parent->m_p_left;
}
if (is_effectively_black(p_w->m_p_right)
&& is_effectively_black(p_w->m_p_left))
{
p_w->m_red = true;
p_x = p_new_x_parent;
p_new_x_parent = p_new_x_parent->m_p_parent;
}
else
{
if (is_effectively_black(p_w->m_p_left))
{
if (p_w->m_p_right != 0)
p_w->m_p_right->m_red = false;
p_w->m_red = true;
base_type::rotate_left(p_w);
p_w = p_new_x_parent->m_p_left;
}
p_w->m_red = p_new_x_parent->m_red;
p_new_x_parent->m_red = false;
if (p_w->m_p_left != 0)
p_w->m_p_left->m_red = false;
base_type::rotate_right(p_new_x_parent);
this->update_to_top(p_new_x_parent, (node_update* )this);
break;
}
}
if (p_x != 0)
p_x->m_red = false;
}