bool skiplist<KEY, VALUE>::erase_impl(NODE *p_cur, KEY &p_key, short p_lvl)
{
if(p_cur->key == p_key)
{
m_delete_ok = true;
return true;
}
if ( p_cur->links[p_lvl] == nullptr || p_cur->links[p_lvl]->key > p_key )
{
if ( p_lvl == 0 )
{
return false;
}
erase_impl ( p_cur, p_key, p_lvl - 1 );
return false;
}
NODE *to_delete {nullptr};
while(p_lvl >= 0 && erase_impl ( p_cur->links[p_lvl], p_key, p_lvl ))
{
to_delete = p_cur->links[p_lvl];
p_cur->links[p_lvl] = to_delete->links[p_lvl];
--p_lvl;
}
return false;
}
iterator erase(const_iterator first, const_iterator last)
{
size_t index = first - begin();
size_t erased_count = 0;
for (; first != last; ++first) ++erased_count;
return erase_impl(index, erased_count);
}
bool skiplist<KEY, VALUE>::erase(KEY p_key)
{
m_delete_ok = false;
erase_impl(m_head, p_key, m_maxLevel - 1);
return m_delete_ok;
}
iterator erase(const_iterator position)
{
return erase_impl(position - begin(), 1);
}
