C++Linux后台开发基础点

GD492-

于 2024-05-25 23:20:29 发布

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文章标签： c++ linux

本文链接：https://blog.youkuaiyun.com/2301_76322993/article/details/139205570

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红黑树

//红黑树节点的定义
enunm colour
{
    RED,
    BLACK,
};

template<class K,class V>
struct RBTreeNode
{
    RBTreeNode<K,V>* _left;
    RBTreeNode<K,V>* _right;
    RBTreeNode<K,V>* _parent;  //三叉链
    pair<K,V> _kv;
    colour _col;
    
    RBTreeeNode(const pair<K,V>& kv)
        	:_left(nullptr)
             ,_right(nullptr)
             ,_parent(nullptr)
             ,_kv(kv)
             ,_col(RED)
            {}  
};

template <class K,class V>
class RBTree
{
    typedef RBTreeNode<K,V>Node;
public:
private:
    Node* _root = nullptr;
};

//红黑树的插入
bool Inert (const pair<K,V>&kv)
{
    if(_root == nullptr)
    {
        _root= new Node(kv);
        return true;
    }
    Node* parent = nullptr;
    Node* cur = _root;
    while(cur)
    {
        if(cur->_kv.first<kv.first) //插入节点比当前节点大往右走，小往左走
        {
            parent = cur;
            cur = cur->right;
        }
        else if(cur->_kv.first> kv.fitst)
        {
            parent = cur;
            cur = cur->left;
        }
        else 
        {
            return false;
        }
    }
    //链接
    cur = new Node(kv);
    if(parent->_kv.first>kv.first)
    {
        parent->_left = cur;
    }
    else 
    {
        parent->_right;
        
    }
    //new的节点的parent还指向空
    cur->_parent = parent;
    
    //插入黑色节点还是红色节点   红色
    	// 如果新插入节点破坏了红黑树规则
	// 则更新节点颜色
	while (parent && parent->_col == RED)
	{
		Node* grandfather = parent->_parent;
		if (grandfather->_left == parent)
		{
			Node* uncle = grandfather->_right;
			// 情况1：u存在且为红，变色处理，并继续往上处理
			if (uncle && uncle->_col == RED)
			{
				parent->_col = BLACK;
				uncle->_col = BLACK;
				grandfather->_col = RED;

				// 继续往上调整
				cur = grandfather;
				parent = cur->_parent;
			}
			else // 情况2+3：u不存在或者u存在且为黑，旋转+处理
			{
				// 如果插入节点在父节点的左，c、p、g呈一条斜线
				//     g
				//   p   u
				// c
				if (parent->_left == cur)
				{
					RotateR(grandfather);
					parent->_col = BLACK;
					grandfather->_col = RED; 
				}
				else
				{
					// 插入节点在父节点的右，c、p、g呈一条折线
					//      g
					//   p      u
					//     c
					RotateL(parent);
					RotateR(grandfather);
					cur->_col = BLACK;
					// parent->_col = RED; // 父亲本就是红，变一下双重保险
					grandfather->_col = RED;
				}

				break;
			}
		}
		else // (grandfather->_right == parent)
		{
			Node* uncle = grandfather->_left;
			// 情况1：u存在且为红，变色处理，并继续往上处理
			if (uncle && uncle->_col == RED)
			{
				parent->_col = BLACK;
				uncle->_col = BLACK;
				grandfather->_col = RED;

				// 继续往上调整
				cur = grandfather;
				parent = cur->_parent;
			}
			else // 情况2+3：u不存在或者u存在且为黑，旋转+处理
			{
				//   g
				// u    p
				//         c
				if (parent->_right == cur)
				{
					RotateL(grandfather);
					grandfather->_col = RED;
					parent->_col = BLACK;
				}
				else
				{
					//   g
					// u     p
					//     c
					RotateR(parent);
					RotateL(grandfather);
					cur->_col = BLACK;
					grandfather->_col = RED;
				}
				break;
			}
		}
	}

	_root->_col = BLACK; // 做个双保险，无论那种情况把根都变成黑的
	return true;
}
}

B和B+树

btree：所有节点存储数据
b树，每次添加都是添加到叶子节点

M阶B树满足条件：
    1.每个节点最多拥有M颗子树
    2.所有叶子节点在同一层
    3.关键字数量满足 （M/2）-1 <= n <= M-1

先进行合并或者借位再删除，分裂在添加时才会出现

#define SUB_M   3

typedef struct _btree_ndoe{
    int *keys;//5
    struct _btree_ndoe **childreds;//6
    
    int num;
    int leaf;
}btree_node;

typedef struct _btree{
    struct _btree_node * root;
}btree;