掌握栈技术，成为技术大神

def quick_sort(arr):
    if len(arr) <= 1:
        return arr
    else:
        pivot = arr[0]
        left = []
        right = []
        for num in arr[1:]:
            if num <= pivot:
                left.append(num)
            else:
                right.append(num)
        return quick_sort(left) + [pivot] + quick_sort(right)

# 使用示例
arr = [3, 6, 8, 10, 1, 2, 1]
sorted_arr = quick_sort(arr)
print(sorted_arr)  # 输出: [1, 1, 2, 3, 6, 8, 10]

function debounce(func, delay) {
    let timer = null;
    return function() {
        const context = this;
        const args = arguments;
        clearTimeout(timer);
        timer = setTimeout(() => {
            func.apply(context, args);
        }, delay);
    };
}

// 使用示例
const searchInput = document.getElementById('search-input');
searchInput.addEventListener('input', debounce(function(e) {
    console.log('搜索:', e.target.value);
    // 这里可以添加搜索逻辑
}, 300));

// 防抖函数可以防止频繁触发，适用于搜索框输入、窗口大小变化等场景

public class BinaryTree {
    private Node root;
    
    private class Node {
        int value;
        Node left;
        Node right;
        
        public Node(int value) {
            this.value = value;
        }
    }
    
    // 插入节点
    public void insert(int value) {
        root = insertRec(root, value);
    }
    
    private Node insertRec(Node root, int value) {
        if (root == null) {
            return new Node(value);
        }
        
        if (value < root.value) {
            root.left = insertRec(root.left, value);
        } else if (value > root.value) {
            root.right = insertRec(root.right, value);
        }
        
        return root;
    }
    
    // 中序遍历
    public void inorderTraversal() {
        inorderRec(root);
    }
    
    private void inorderRec(Node root) {
        if (root != null) {
            inorderRec(root.left);
            System.out.print(root.value + " ");
            inorderRec(root.right);
        }
    }
    
    // 测试代码
    public static void main(String[] args) {
        BinaryTree tree = new BinaryTree();
        tree.insert(50);
        tree.insert(30);
        tree.insert(20);
        tree.insert(40);
        tree.insert(70);
        tree.insert(60);
        tree.insert(80);
        
        tree.inorderTraversal(); // 输出: 20 30 40 50 60 70 80
    }
}

-- 创建用户表
CREATE TABLE users (
    id INT PRIMARY KEY AUTO_INCREMENT,
    username VARCHAR(50) NOT NULL UNIQUE,
    email VARCHAR(100) NOT NULL UNIQUE,
    password_hash VARCHAR(100) NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
);

-- 创建文章表
CREATE TABLE articles (
    id INT PRIMARY KEY AUTO_INCREMENT,
    title VARCHAR(200) NOT NULL,
    content TEXT NOT NULL,
    user_id INT NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
);

-- 查询用户及其发表的文章
SELECT users.username, articles.title, articles.content
FROM users
JOIN articles ON users.id = articles.user_id
WHERE users.username = 'john_doe';

-- 添加全文搜索索引
ALTER TABLE articles ADD FULLTEXT(title, content);

-- 使用全文搜索
SELECT * FROM articles
WHERE MATCH(title, content) AGAINST('技术教程' IN NATURAL LANGUAGE MODE);