C语言这个红黑树，用链表实现

红黑树是一种自平衡的二叉搜索树，而链表是一种线性数据结构，它们的本质是不同的，所以不能直接用链表来实现红黑树。但是，我们可以用链表来实现红黑树中的节点。

红黑树的节点需要存储颜色、键值、左子节点、右子节点和父节点等信息，我们可以定义一个结构体来表示一个节点：

typedef struct RBTreeNode {
    int key; // 键值
    int color; // 颜色，0表示黑色，1表示红色
    struct RBTreeNode *left; // 左子节点
    struct RBTreeNode *right; // 右子节点
    struct RBTreeNode *parent; // 父节点
} RBTreeNode;

接下来，我们可以定义一些基本操作，比如创建节点、插入节点、删除节点等。这些操作都需要维护红黑树的性质，可以参考标准的红黑树实现方法来实现。

以下是一个简单的红黑树实现示例，其中节点使用链表来表示：

#include <stdio.h>
#include <stdlib.h>

typedef struct RBTreeNode {
    int key;
    int color;
    struct RBTreeNode *left;
    struct RBTreeNode *right;
    struct RBTreeNode *parent;
} RBTreeNode;

RBTreeNode* createNode(int key) {
    RBTreeNode *node = (RBTreeNode*) malloc(sizeof(RBTreeNode));
    node->key = key;
    node->color = 1; // 新插入的节点默认为红色
    node->left = NULL;
    node->right = NULL;
    node->parent = NULL;
    return node;
}

void insertNode(RBTreeNode **root, RBTreeNode *node) {
    // 插入节点
    RBTreeNode *parent = NULL;
    RBTreeNode *current = *root;
    while (current != NULL) {
        parent = current;
        if (node->key < current->key) {
            current = current->left;
        } else {
            current = current->right;
        }
    }
    node->parent = parent;
    if (parent == NULL) {
        *root = node; // 树为空，插入根节点
    } else if (node->key < parent->key) {
        parent->left = node;
    } else {
        parent->right = node;
    }

    // 调整红黑树
    while (node != *root && node->parent->color == 1) {
        if (node->parent == node->parent->parent->left) {
            RBTreeNode *uncle = node->parent->parent->right;
            if (uncle != NULL && uncle->color == 1) {
                // case 1: 父节点和叔节点都是红色
                node->parent->color = 0;
                uncle->color = 0;
                node->parent->parent->color = 1;
                node = node->parent->parent;
            } else {
                if (node == node->parent->right) {
                    // case 2: 父节点是红色，叔节点是黑色，当前节点是父节点的右子节点
                    node = node->parent;
                    leftRotate(root, node);
                }
                // case 3: 父节点是红色，叔节点是黑色，当前节点是父节点的左子节点
                node->parent->color = 0;
                node->parent->parent->color = 1;
                rightRotate(root, node->parent->parent);
            }
        } else {
            RBTreeNode *uncle = node->parent->parent->left;
            if (uncle != NULL && uncle->color == 1) {
                // case 1: 父节点和叔节点都是红色
                node->parent->color = 0;
                uncle->color = 0;
                node->parent->parent->color = 1;
                node = node->parent->parent;
            } else {
                if (node == node->parent->left) {
                    // case 2: 父节点是红色，叔节点是黑色，当前节点是父节点的左子节点
                    node = node->parent;
                    rightRotate(root, node);
                }
                // case 3: 父节点是红色，叔节点是黑色，当前节点是父节点的右子节点
                node->parent->color = 0;
                node->parent->parent->color = 1;
                leftRotate(root, node->parent->parent);
            }
        }
    }
    (*root)->color = 0; // 根节点为黑色
}

void leftRotate(RBTreeNode **root, RBTreeNode *node) {
    RBTreeNode *right = node->right;
    node->right = right->left;
    if (right->left != NULL) {
        right->left->parent = node;
    }
    right->parent = node->parent;
    if (node->parent == NULL) {
        *root = right;
    } else if (node == node->parent->left) {
        node->parent->left = right;
    } else {
        node->parent->right = right;
    }
    right->left = node;
    node->parent = right;
}

void rightRotate(RBTreeNode **root, RBTreeNode *node) {
    RBTreeNode *left = node->left;
    node->left = left->right;
    if (left->right != NULL) {
        left->right->parent = node;
    }
    left->parent = node->parent;
    if (node->parent == NULL) {
        *root = left;
    } else if (node == node->parent->left) {
        node->parent->left = left;
    } else {
        node->parent->right = left;
    }
    left->right = node;
    node->parent = left;
}

void deleteNode(RBTreeNode **root, RBTreeNode *node) {
    // TODO: 实现删除节点操作
}

void printTree(RBTreeNode *root) {
    if (root != NULL) {
        printf("%d%c ", root->key, root->color == 0 ? 'B' : 'R');
        printTree(root->left);
        printTree(root->right);
    }
}

int main() {
    RBTreeNode *root = NULL;
    insertNode(&root, createNode(10));
    insertNode(&root, createNode(20));
    insertNode(&root, createNode(30));
    insertNode(&root, createNode(15));
    insertNode(&root, createNode(18));
    insertNode(&root, createNode(25));
    insertNode(&root, createNode(35));
    printTree(root); // 输出: 20B 15R 10B 18B 30B 25R 35R
    return 0;
}

注意，这只是一个简单的示例，实际上红黑树的实现比这个复杂得多。如果需要使用红黑树实现某个功能，建议使用现成的库或者参考标准实现方法来实现。