数据结构解析:栈、队列与树

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"计算机专业英语-chapter-04.ppt - 数据结构章节" 在计算机科学中,数据结构是组织和管理数据的重要工具,它能够提升程序的效率、抽象复杂问题并实现代码的复用性。本章主要探讨了数据结构中的关键概念、难点以及学习要求。 首先,使用数据结构的主要原因有三个:效率、抽象和复用性。效率体现在通过合适的数据结构选择,可以优化算法的性能,降低时间和空间复杂度。抽象则是将复杂问题简化,用数据结构来代表现实世界中的实体或关系。复用性则意味着设计好的数据结构可以在不同的场景下重复使用,减少代码编写的工作量。 接着,本章提到了三个关键的数据结构:栈、队列和树。栈是一种后进先出(LIFO)的数据结构,常用于函数调用、表达式求值等场景。队列则是一种先进先出(FIFO)的数据结构,常见于任务调度、打印队列等应用。而树是一种非线性的数据结构,能够表示层次关系,如文件系统、HTML DOM等。 在学习要求方面,你需要了解栈、队列和树的基本属性,并掌握如何在英语环境中准确地描述这些概念。例如,哈希表(hashtable)是一种快速查找的数据结构,通过散列函数将数据映射到固定大小的数组中;优先队列(priority queues)处理元素时考虑优先级,通常用于调度任务;复用性(reusability)强调代码的可重用性,提高软件开发效率;二叉树(binary tree)每个节点最多有两个子节点,常用于搜索和排序操作;遍历(traversing)是指按照某种顺序访问树的所有节点;而“context-free”通常与上下文无关文法相关,是编译原理中的概念。 此外,学习新词汇和表达也是本章的重点,比如哈希表(hashtable)、优先队列(priority queues)、复用性(reusability)、二叉树(binary tree)、遍历(traversing)等。理解这些术语及其在实际编程中的应用,对于深入理解数据结构至关重要。 本章旨在帮助你理解数据结构的基本概念,熟悉常见的数据结构类型及其特点,同时提升你的专业英语水平,以便更好地阅读和理解英文技术文档,进而提升你在IT领域的专业素养。

7.main方法参数的使用。阅读下面的代码。 --------程序清单------------------------------------------------------------------------------------------------------------ package chapter06; public class CommandLine { public static void main(String[] args) { if (args.length == 0) { System.out.println("Hello, welcome to Java!"); } else { switch (args[0]) { case "-draw" -> { for (int i = 0; i < 3; i++) { for (int j = i; j < 3; j++) System.out.print("*"); System.out.println(); } } case "-add" -> {// + int sum = 0; for (int i = 1; i < args.length; i++) { int num = Integer.parseInt(args[i]); sum += num; if (i != 1 && num > 0) System.out.print("+"); System.out.print(args[i]); } System.out.println("=" + sum); } default -> { System.out.println("no such command-line option"); } } } } } --------------------------------------------------------------------------------------------------------------------------------- 以下操作都在该类源文件所在的文件夹下。 (a)(2分)编译完该类后,如果在终端通过输入命令“java chapter06.CommandLine -cdl Wenzhou”运行该类,此时main方法的形参args其每个元素的值是什么? (b)(16分)分别通过以下命令运行该程序,其输出结果是什么?请简单说明你的理由(没有理由不给分)。 java chapter06.CommandLine -add 12 31 44 -1 -2 java chapter06.CommandLine -draw java chapter06.CommandLine java chapter06.CommandLine -cdl (c)(2分)在Eclipse里设置运行配置,然后得到(b)中第1条命令运行效果并截图。 答:

2023-05-25 上传

xiazai.py:10:0: C0301: Line too long (130/100) (line-too-long) xiazai.py:29:21: C0303: Trailing whitespace (trailing-whitespace) xiazai.py:30:0: W0311: Bad indentation. Found 10 spaces, expected 12 (bad-indentation) xiazai.py:40:0: C0301: Line too long (103/100) (line-too-long) xiazai.py:41:0: C0301: Line too long (153/100) (line-too-long) xiazai.py:53:0: C0305: Trailing newlines (trailing-newlines) xiazai.py:1:0: C0114: Missing module docstring (missing-module-docstring) xiazai.py:7:0: C0103: Constant name "url" doesn't conform to UPPER_CASE naming style (invalid-name) xiazai.py:13:13: W3101: Missing timeout argument for method 'requests.get' can cause your program to hang indefinitely (missing-timeout) xiazai.py:14:16: I1101: Module 'lxml.etree' has no 'HTML' member, but source is unavailable. Consider adding this module to extension-pkg-allow-list if you want to perform analysis based on run-time introspection of living objects. (c-extension-no-member) xiazai.py:19:0: C0103: Constant name "num" doesn't conform to UPPER_CASE naming style (invalid-name) xiazai.py:21:4: R1723: Unnecessary "elif" after "break", remove the leading "el" from "elif" (no-else-break) xiazai.py:24:17: W3101: Missing timeout argument for method 'requests.get' can cause your program to hang indefinitely (missing-timeout) xiazai.py:25:20: I1101: Module 'lxml.etree' has no 'HTML' member, but source is unavailable. Consider adding this module to extension-pkg-allow-list if you want to perform analysis based on run-time introspection of living objects. (c-extension-no-member) xiazai.py:28:8: C0103: Constant name "judge" doesn't conform to UPPER_CASE naming style (invalid-name) xiazai.py:28:31: C0209: Formatting a regular string which could be a f-string (consider-using-f-string) xiazai.py:30:22: C0209: Formatting a regular string which could be a f-string (consider-using-f-string) xiazai.py:31:14: C0209: Formatting a regular string which could be a f-string (consider-using-f-string) xiazai.py:34:8: C0103: Constant name "chapter_num" doesn't conform to UPPER_CASE naming style (invalid-name) xiazai.py:38:29: W3101: Missing timeout argument for method 'requests.get' can cause your program to hang indefinitely (missing-timeout) xiazai.py:39:32: I1101: Module 'lxml.etree' has no 'HTML' member, but source is unavailable. Consider adding this module to extension-pkg-allow-list if you want to perform analysis based on run-time introspection of living objects. (c-extension-no-member) xiazai.py:41:22: C0209: Formatting a regular string which could be a f-string (consider-using-f-string) xiazai.py:42:16: C0103: Constant name "all_content" doesn't conform to UPPER_CASE naming style (invalid-name) xiazai.py:44:20: R1713: Consider using str.join(sequence) for concatenating strings from an iterable (consider-using-join) ----------------------------------- Your code has been rated at 5.43/10

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