_tree.c

MONA是为数不多的C++语言编写的一个很小的操作系统

    
    __z = _M_create_node(__v);
    _S_left(__y) = __z;               // also makes _M_leftmost() = __z 
                                      //    when __y == _M_header
    if (__y == this->_M_header._M_data) {
      _M_root() = __z;
      _M_rightmost() = __z;
    }
    else if (__y == _M_leftmost())
      _M_leftmost() = __z;   // maintain _M_leftmost() pointing to min node
  }
  else {
    __z = _M_create_node(__v);
    _S_right(__y) = __z;
    if (__y == _M_rightmost())
      _M_rightmost() = __z;  // maintain _M_rightmost() pointing to max node
  }
  _S_parent(__z) = __y;
  _S_left(__z) = 0;
  _S_right(__z) = 0;
  _Rb_global_inst::_Rebalance(__z, this->_M_header._M_data->_M_parent);
  ++_M_node_count;
  return iterator(__z);
}

template <class _Key, class _Value, class _KeyOfValue, 
          class _Compare, class _Alloc> __iterator__
_Rb_tree<_Key,_Value,_KeyOfValue,_Compare,_Alloc> ::insert_equal(const _Value& __v)
{
  _Link_type __y = this->_M_header._M_data;
  _Link_type __x = _M_root();
  while (__x != 0) {
    __y = __x;
    __x = _M_key_compare(_KeyOfValue()(__v), _S_key(__x)) ? 
            _S_left(__x) : _S_right(__x);
  }
  return _M_insert(__x, __y, __v);
}


template <class _Key, class _Value, class _KeyOfValue, 
          class _Compare, class _Alloc> pair< _Rb_tree_iterator<_Value, _Nonconst_traits<_Value> >, bool> _Rb_tree<_Key,_Value,_KeyOfValue,_Compare,_Alloc> ::insert_unique(const _Value& __v)
{
  _Link_type __y = this->_M_header._M_data;
  _Link_type __x = _M_root();
  bool __comp = true;
  while (__x != 0) {
    __y = __x;
    __comp = _M_key_compare(_KeyOfValue()(__v), _S_key(__x));
    __x = __comp ? _S_left(__x) : _S_right(__x);
  }
  iterator __j = iterator(__y);   
  if (__comp)
    if (__j == begin())     
      return pair<iterator,bool>(_M_insert(/* __x*/ __y, __y, __v), true);
    else
      --__j;
  if (_M_key_compare(_S_key(__j._M_node), _KeyOfValue()(__v)))
    return pair<iterator,bool>(_M_insert(__x, __y, __v), true);
  return pair<iterator,bool>(__j, false);
}

// Modifications CRP 7/10/00 as noted to improve conformance and
// efficiency.
template <class _Key, class _Value, class _KeyOfValue, 
          class _Compare, class _Alloc> __iterator__ 
_Rb_tree<_Key, _Value, _KeyOfValue, _Compare, _Alloc> ::insert_unique(iterator __position, const _Value& __v)
{
  if (__position._M_node == this->_M_header._M_data->_M_left) { // begin()

    // if the container is empty, fall back on insert_unique.
    if (size() <= 0)
      return insert_unique(__v).first;

    if ( _M_key_compare(_KeyOfValue()(__v), _S_key(__position._M_node)))
      return _M_insert(__position._M_node, __position._M_node, __v);
    // first argument just needs to be non-null 
    else
      {
	bool __comp_pos_v = _M_key_compare( _S_key(__position._M_node), _KeyOfValue()(__v) );
	
	if (__comp_pos_v == false)  // compare > and compare < both false so compare equal
	  return __position;
	//Below __comp_pos_v == true

	// Standard-conformance - does the insertion point fall immediately AFTER
	// the hint?
	iterator __after = __position;
	++__after;

	// Check for only one member -- in that case, __position points to itself,
	// and attempting to increment will cause an infinite loop.
	if (__after._M_node == this->_M_header._M_data)
	  // Check guarantees exactly one member, so comparison was already
	  // performed and we know the result; skip repeating it in _M_insert
	  // by specifying a non-zero fourth argument.
	  return _M_insert(0, __position._M_node, __v, __position._M_node);
		
	
	// All other cases:
	
	// Optimization to catch insert-equivalent -- save comparison results,
	// and we get this for free.
	if(_M_key_compare( _KeyOfValue()(__v), _S_key(__after._M_node) )) {
	  if (_S_right(__position._M_node) == 0)
	    return _M_insert(0, __position._M_node, __v, __position._M_node);
	  else
	    return _M_insert(__after._M_node, __after._M_node, __v);
	} else {
	    return insert_unique(__v).first;
	}
      }

  } else if (__position._M_node == this->_M_header._M_data) { // end()
    if (_M_key_compare(_S_key(_M_rightmost()), _KeyOfValue()(__v)))
      // pass along to _M_insert that it can skip comparing
      // v, Key ; since compare Key, v was true, compare v, Key must be false.
      return _M_insert(0, _M_rightmost(), __v, __position._M_node); // Last argument only needs to be non-null
    else
      return insert_unique(__v).first;
  } else {
    iterator __before = __position;
    --__before;
    
    bool __comp_v_pos = _M_key_compare(_KeyOfValue()(__v), _S_key(__position._M_node));

    if (__comp_v_pos
      && _M_key_compare( _S_key(__before._M_node), _KeyOfValue()(__v) )) {

      if (_S_right(__before._M_node) == 0)
        return _M_insert(0, __before._M_node, __v, __before._M_node); // Last argument only needs to be non-null
      else
        return _M_insert(__position._M_node, __position._M_node, __v);
    // first argument just needs to be non-null 
    } else
      {
	// Does the insertion point fall immediately AFTER the hint?
	iterator __after = __position;
	++__after;
	
	// Optimization to catch equivalent cases and avoid unnecessary comparisons
	bool __comp_pos_v = !__comp_v_pos;  // Stored this result earlier
	// If the earlier comparison was true, this comparison doesn't need to be
	// performed because it must be false.  However, if the earlier comparison
	// was false, we need to perform this one because in the equal case, both will
	// be false.
	if (!__comp_v_pos) __comp_pos_v = _M_key_compare(_S_key(__position._M_node), _KeyOfValue()(__v));
	
	if ( (!__comp_v_pos) // comp_v_pos true implies comp_v_pos false
	     && __comp_pos_v
	     && (__after._M_node == this->_M_header._M_data ||
	        _M_key_compare( _KeyOfValue()(__v), _S_key(__after._M_node) ))) {
	  
	  if (_S_right(__position._M_node) == 0)
	    return _M_insert(0, __position._M_node, __v, __position._M_node);
	  else
	    return _M_insert(__after._M_node, __after._M_node, __v);
	} else {
	  // Test for equivalent case
	  if (__comp_v_pos == __comp_pos_v)
	    return __position;
	  else
	    return insert_unique(__v).first;
	}
      }
  }
}


template <class _Key, class _Value, class _KeyOfValue, 
          class _Compare, class _Alloc> __iterator__ 
_Rb_tree<_Key,_Value,_KeyOfValue,_Compare,_Alloc> ::insert_equal(iterator __position, const _Value& __v)
{
  if (__position._M_node == this->_M_header._M_data->_M_left) { // begin()

    // Check for zero members
    if (size() <= 0)
        return insert_equal(__v);

    if (!_M_key_compare(_S_key(__position._M_node), _KeyOfValue()(__v)))
      return _M_insert(__position._M_node, __position._M_node, __v);
    else    {
      // Check for only one member
      if (__position._M_node->_M_left == __position._M_node)
        // Unlike insert_unique, can't avoid doing a comparison here.
        return _M_insert(0, __position._M_node, __v);
                
      // All other cases:
      // Standard-conformance - does the insertion point fall immediately AFTER
      // the hint?
      iterator __after = __position;
      ++__after;
      
      // Already know that compare(pos, v) must be true!
      // Therefore, we want to know if compare(after, v) is false.
      // (i.e., we now pos < v, now we want to know if v <= after)
      // If not, invalid hint.
      if ( __after._M_node==this->_M_header._M_data ||
	   !_M_key_compare( _S_key(__after._M_node), _KeyOfValue()(__v) ) ) {
        if (_S_right(__position._M_node) == 0)
          return _M_insert(0, __position._M_node, __v, __position._M_node);
        else
          return _M_insert(__after._M_node, __after._M_node, __v);
      } else // Invalid hint
        return insert_equal(__v);
    }
  } else if (__position._M_node == this->_M_header._M_data) {// end()
    if (!_M_key_compare(_KeyOfValue()(__v), _S_key(_M_rightmost())))
      return _M_insert(0, _M_rightmost(), __v, __position._M_node); // Last argument only needs to be non-null
    else
      return insert_equal(__v);
  } else {
    iterator __before = __position;
    --__before;
    // store the result of the comparison between pos and v so
    // that we don't have to do it again later.  Note that this reverses the shortcut
    // on the if, possibly harming efficiency in comparisons; I think the harm will
    // be negligible, and to do what I want to do (save the result of a comparison so
    // that it can be re-used) there is no alternative.  Test here is for before <= v <= pos.
    bool __comp_pos_v = _M_key_compare(_S_key(__position._M_node), _KeyOfValue()(__v));
    if (!__comp_pos_v
        && !_M_key_compare(_KeyOfValue()(__v), _S_key(__before._M_node))) {
      if (_S_right(__before._M_node) == 0)
        return _M_insert(0, __before._M_node, __v, __before._M_node); // Last argument only needs to be non-null
      else
        return _M_insert(__position._M_node, __position._M_node, __v);
    } else  {
      // Does the insertion point fall immediately AFTER the hint?
      // Test for pos < v <= after
      iterator __after = __position;
      ++__after;
      
      if (__comp_pos_v
	  && ( __after._M_node==this->_M_header._M_data 
	       || !_M_key_compare( _S_key(__after._M_node), _KeyOfValue()(__v) ) ) ) {
        if (_S_right(__position._M_node) == 0)
          return _M_insert(0, __position._M_node, __v, __position._M_node);
        else
          return _M_insert(__after._M_node, __after._M_node, __v);
      } else // Invalid hint
        return insert_equal(__v);
    }
  }
}

template <class _Key, class _Value, class _KeyOfValue, class _Compare, class _Alloc> _Rb_tree_node<_Value>* 
_Rb_tree<_Key,_Value,_KeyOfValue,_Compare,_Alloc> ::_M_copy(_Rb_tree_node<_Value>* __x, _Rb_tree_node<_Value>* __p)
{
                        // structural copy.  __x and __p must be non-null.
  _Link_type __top = _M_clone_node(__x);
  __top->_M_parent = __p;
  
  _STLP_TRY {
    if (__x->_M_right)
      __top->_M_right = _M_copy(_S_right(__x), __top);
    __p = __top;
    __x = _S_left(__x);

    while (__x != 0) {
      _Link_type __y = _M_clone_node(__x);
      __p->_M_left = __y;
      __y->_M_parent = __p;
      if (__x->_M_right)
        __y->_M_right = _M_copy(_S_right(__x), __y);
      __p = __y;
      __x = _S_left(__x);
    }
  }
  _STLP_UNWIND(_M_erase(__top));

  return __top;
}

// this has to stay out-of-line : it's recursive
template <class _Key, class _Value, class _KeyOfValue, 
          class _Compare, class _Alloc> void 
_Rb_tree<_Key,_Value,_KeyOfValue,
  _Compare,_Alloc>::_M_erase(_Rb_tree_node<_Value>* __x)
{
                                // erase without rebalancing
  while (__x != 0) {
    _M_erase(_S_right(__x));
    _Link_type __y = _S_left(__x);
    _STLP_STD::_Destroy(&__x->_M_value_field);
    this->_M_header.deallocate(__x,1);
    __x = __y;
  }
}

template <class _Key, class _Value, class _KeyOfValue, 
          class _Compare, class _Alloc> __size_type__ 
_Rb_tree<_Key,_Value,_KeyOfValue,_Compare,_Alloc> ::count(const _Key& __k) const
{
  pair<const_iterator, const_iterator> __p = equal_range(__k);
  size_type __n = distance(__p.first, __p.second);
  return __n;
}

inline int 
__black_count(_Rb_tree_node_base* __node, _Rb_tree_node_base* __root)
{
  if (__node == 0)
    return 0;
  else {
    int __bc = __node->_M_color == _S_rb_tree_black ? 1 : 0;
    if (__node == __root)
      return __bc;
    else
      return __bc + __black_count(__node->_M_parent, __root);
  }
}

template <class _Key, class _Value, class _KeyOfValue, 
          class _Compare, class _Alloc> bool _Rb_tree<_Key,_Value,_KeyOfValue,_Compare,_Alloc>::__rb_verify() const
{
  if (_M_node_count == 0 || begin() == end())
    return _M_node_count == 0 && begin() == end() && this->_M_header._M_data->_M_left == this->_M_header._M_data
      && this->_M_header._M_data->_M_right == this->_M_header._M_data;
  
  int __len = __black_count(_M_leftmost(), _M_root());
  for (const_iterator __it = begin(); __it != end(); ++__it) {
    _Link_type __x = (_Link_type) __it._M_node;
    _Link_type __L = _S_left(__x);
    _Link_type __R = _S_right(__x);

    if (__x->_M_color == _S_rb_tree_red)
      if ((__L && __L->_M_color == _S_rb_tree_red) ||
          (__R && __R->_M_color == _S_rb_tree_red))
        return false;

    if (__L && _M_key_compare(_S_key(__x), _S_key(__L)))
      return false;
    if (__R && _M_key_compare(_S_key(__R), _S_key(__x)))
      return false;

    if (!__L && !__R && __black_count(__x, _M_root()) != __len)
      return false;
  }

  if (_M_leftmost() != _Rb_tree_node_base::_S_minimum(_M_root()))
    return false;
  if (_M_rightmost() != _Rb_tree_node_base::_S_maximum(_M_root()))
    return false;

  return true;
}
_STLP_END_NAMESPACE

# undef __iterator__        
# undef iterator
# undef __size_type__  

#endif /*  _STLP_TREE_C */

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// mode:C++
// End: