"数据结构教学课件：Chapter7.ppt中的排序算法与性能分析"

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Sorting is a fundamental concept in the field of data structures. It involves arranging a sequence of records with key values into a specific order, such that the keys follow a particular property. The process of sorting requires comparison of the keys and can be measured in terms of the number of comparisons made. The key concept in sorting is to arrange the records in such a way that the keys obey the property ks1 ≤ ks2 ≤ …≤ ksn. Each record contains a field called the key, which is used for comparison during the sorting process. The comparison of keys is essential for determining the order in which the records are arranged. There are various methods and algorithms for sorting, each with its own advantages and disadvantages. Some popular sorting algorithms include bubble sort, selection sort, insertion sort, merge sort, and quicksort. Each of these algorithms has different efficiencies in terms of time complexity, space complexity, and stability. The cost of sorting is measured in terms of the number of comparisons made during the process. The efficiency of a sorting algorithm is often evaluated based on the number of comparisons it requires to sort a given sequence of records. The fewer the comparisons, the more efficient the algorithm is considered to be. In conclusion, sorting is an important concept in data structures and is essential for organizing and managing large amounts of data. The process involves arranging records in a specific order based on their key values, and the efficiency of sorting algorithms can be measured in terms of the number of comparisons required. Understanding the different sorting algorithms and their efficiencies is crucial for effectively managing and manipulating data in various applications.

数据结构教学课件：Chapter7

2022-05-17 上传
数据结构教学课件：Chapter7

数据结构课件：第7章 图.ppt

2022-06-16 上传
数据结构课件：第7章 图.ppt

数据结构课件：第7章 图.ppt

2022-07-04 上传
数据结构课件：第7章 图.ppt

java: 不兼容的类型: chapter11.gui.OKActionListener无法转换为java.awt.event.ActionListener

2023-05-26 上传
这个错误通常出现在你试图将一个类型为 `chapter11.gui.OKActionListener` 的对象赋值给一个类型为 `java.awt.event.ActionListener` 的变量或将其作为参数传递给一个接受 `java.awt.event.ActionListener` 类型的...

volume 1 :chapter 1. cyclone iv fpga 器件系列概述

2023-06-06 上传
其中，Cyclone IV GX系列具有高速串行收发器和高速DDR3接口，适合于高速数据传输和嵌入式高端图像处理应用；Cyclone IV E系列则针对一般应用提供了一种经济实惠的解决方案，集成了许多常用接口和外设，既保留了...

import requests import os from bs4 import BeautifulSoup class book_spider(): def __init__(self,root_url): self.root_url=root_url self.book_list=[] #一级页面中获取的数据（二级页面地址）存放于此列表 self.chapter_list=[] #二级页面中获取的数据（三级页面地址和章节名）存放于此列表 def get_url(url): while True: try: res=requests.get(url) if res.status_code==200: res.encoding =res.apparent_encoding print("页面获取成功") return res.text else: print("页面返回异常",res.status_code) except: print("页面获取错误") def get_book_list(self.url): res = self.get_url(url) html = BeautifulSoup(res,"html.parser") a_list = html.find_all("a",{"class":"name"}) for a in a_list: self.book_list.append(a["href"]) self.book_list = [self.root_url+i for i in self.bbok_list] self.book_list.remove('http://10.1.88.252:7000/庆余年') print(book_list) def get_chapter_list(self,url): res = self.get_url(url) html = BeautifulSoup(res,"html.parser") a_list = html.find_all("a",{"class":"chapter"}) for a in a_list: self.chapter_list.append((a["href"],a.text.replace("\n",""))) def get_content(self.chapter): url = self.root_url + chapter[0] print(url) book_name = chapter[0].split("/")[1] print(book_name) if not os.path.exists(book_name): os.mkdir(book_name) res = self.get_url(url) html = BeautifulSoup(res,"html.parser") content = html.find("div",{"id":"content"}).text print(content) path = os.path.join(book_name,chapter[1]) with open(path,"w",encoding="utf8") as f: f.write(content) def main(): self.get_book_list(self.root_url) for book in self.book_list: self.get_chapter_liat(book) for chapter in chapter_list: self.get_content(chapter) book_s = book_spider("http://10.1.88.252:7000") book_s.main()这是一段爬虫代码，找出里面的错误并改正

2023-06-02 上传
4. 在 `get_chapter_list` 方法中，将 `self.chapter_list.append((a["href"],a.text.replace("\n","")))` 改为 `self.chapter_list.append((self.root_url+a["href"],a.text.replace("\n","")))`，因为需要获取完整...

idea报错 org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.wlz.chapter.mapper.ArticleMapper.selectArticle

2024-04-15 上传
在你提供的错误信息中，报错信息是"Invalid bound statement (not found): com.wlz.chapter.mapper.ArticleMapper.selectArticle"，意思是无效的绑定语句（未找到）。 这个错误通常是由于MyBatis配置文件中的映射...

帮我把一下代码设置一个合理请求头，并加入一个延时import requests import os from bs4 import BeautifulSoup class NovelDownloader: def __init__(self, root_url): self.root_url = root_url self.book_list = [] self.chapter_list = [] def get_url(self, url): while True: try: res = requests.get(url) if res.status_code == 200: print("页面获取成功！") return res.text else: print("页面返回异常！", res.status_code) except: print("页面获取错误！") def get_book_list(self): res = self.get_url(self.root_url) html = BeautifulSoup(res, "html.parser") a_list = html.find_all("a", {"class": "name"}) for a in a_list: self.book_list.append(a["href"]) self.book_list = [self.root_url + i for i in self.book_list] self.book_list.remove('http://www.biquge5200.cc/') def get_chapter_list(self, url): res = self.get_url(url) html = BeautifulSoup(res, "html.parser") a_list = html.find_all("a", {"class": "chapter"}) for a in a_list: self.chapter_list.append((a["href"], a.text.replace("\n", ""))) def get_content(self, chapter): url = self.root_url + chapter[0] print(url) book_name = chapter[0].split("/")[1] print(book_name) if not os.path.exists(book_name): os.mkdir(book_name) res = self.get_url(url) html = BeautifulSoup(res, "html.parser") content = html.find("div", {"id": "content"}).text print(content) path = os.path.join(book_name, chapter[1]) with open(path, "w", encoding="utf8") as f: f.write(content) def main(self): self.get_book_list() for book in self.book_list: self.get_chapter_list(book) for chapter in self.chapter_list: self.get_content(chapter) if __name__ == '__main__': root_url = "http://www.biquge5200.cc/" nd = NovelDownloader(root_url) nd.main()

2023-06-02 上传
for chapter in self.chapter_list: self.get_content(chapter) if __name__ == '__main__': root_url = "http://www.biquge5200.cc/" nd = NovelDownloader(root_url) nd.main() ``` 这样就可以更好地模拟...

package chapter0204; import java.util.Scanner; public class department { public static void main (String[] args) { /* * 根据用户输入的信息确定员工应分配到那个部门。 */ Scanner sc =new Scanner(System.in); System.out.println("请输入新员工的姓名："); String name=sc.next(); System.out.println("请输入新员工应聘的语言："); String language=sc.next(); switch(language){ case "Java": case "java": System.out.println(name+"被分配到java程序开发部门"); break; case "C#": case "c#": System.out.println(name+"被分配到c#程序开发部门"); break; case "asp.net": System.out.println(name+"被分配到asp.net程序测试部门"); break; case "html": case "Html": System.out.println(name+"被分配到前端程序开发部门"); break; default: System.out.println("抱歉，本公司不需要"+language+"语言的人。"); break; } } }解释这段代码

2023-03-27 上传
++": case "c++": System.out.println(name + "被分配到C++程序开发部门"); break; case "Python": case "python": System.out.println(name + "被分配到Python程序开发部门"); break; default: System.out.println...

Traceback (most recent call last): File "C:/Users/Administrator/Desktop/chapter5/chapter5/demo/code/logistic_regression.py", line 10, in <module> x = data.iloc[:,:8].as_matrix() File "C:\ProgramData\Anaconda3\lib\site-packages\pandas\core\generic.py", line 5274, in __getattr__ return object.__getattribute__(self, name) AttributeError: 'DataFrame' object has no attribute 'as_matrix'，这个怎么解决

2023-05-25 上传
这个错误是因为Pandas库中的DataFrame对象已经没有as_matrix()方法了，可以用values属性来代替as_matrix()方法，将data.iloc[:,:8].as_matrix()改为data.iloc[:,:8].values即可。例如： ``` x = data.iloc[:,:8]....
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