142. 环形链表 II

题目链接：https://leetcode.cn/problems/linked-list-cycle-ii/description/我的思路第一次遇到这种题，有点被吓到了，不知道什么是链表，被题目里的定义和复杂的描述给唬住了，一直在纠结给出代码中的ListNode类的定义是什么，读懂题意花了很长时间，没有自己的解答思路纠正理解题意：给的链表其实就是有序的列表，然后这道题里在有序的列表基础上形成了环，那么这种结构就会涉及到几个新的元素：链表起点（叫做头，head）、环的起点（题目里pos给出了环起点的索引），自己一开始感到奇怪，明明给了链表的环起点pos，为什么还要判断是否有环以及求环的起点索引？因为题目里很明确地说了，pos变量不会作为参数进行传递，是评测系统内部的一个参数，表示链表尾链接到链表中的位置，只是为了标识链表的实际情况，因此这只是一个让我们知道这个链表有没有环结构的一个标志，对我们的实际问题求解不会有什么影响和帮助，那么我们要怎么判断这个链表是否存在环呢？题目里也很明确地告诉我们了，只要链表中后续还有节点，就可以一直使用.next指针到达，同时如果这个过程能够一直循环下去

双指针 · 04-06

88. 合并两个有序数组

我的思路直接尝试赋新值给nums1=nums1[:m]+nums2，但在Leetcode的运行环境中，这样的办法行不通，只是重新绑定了一个新的列表对象，原先的nums1并没有被改变，在测试的时候后台会检查原先的nums1是否有被修改，因此这种办法是行不通的，需要在原数组上一个个修改数值才行纠正还是需要用双指针的思路，判断值，然后把值填进表中初始化三个指针，分别定位在nums1（短）、nums2和nums1（长）的最后一个元素，对应的索引值分别为m-1, n-1, m+n-1，接下来依次开始判断nums1（短）和nums2的元素大小，把更大的那个放到nums1（长）的后面，这也是为什么要有第三个指针的原因，因为我们需要修改的是原始nums1例子：nums1 = [1,2,3,0,0,0,0], m = 3, nums2 = [2,4,5,7], n = 4思路：初始化三个指针的值分别为p = 2, q = 3, pos = 6，从左右边开始：判断nums1[2]和nums2[3]的大小，7>3，所以把7放到nums1[6]，此时已经将nums2[3]的这个元素用掉了，所以要把num

双指针 · 04-03

VLC中的常见术语

上学期组会中一次文献分享提到了VLC中的常见术语，包含了器件、技术等主题，下面对这些名词做一些解释和理解：Underwater 含义: 水下可见光通信介绍: 利用可见光在水下环境中进行数据传输技术Software Pre-Equalizer:含义: 软件预均衡器介绍: 在信号传输前对其进行处理，以减少失真PIN Array:含义: PIN 二极管阵列介绍: PIN 二极管是一种光电探测器，用于将光信号转换为电信号阵列形式可以提高接收灵敏度和覆盖范围LSC:含义: Light-to-Signal Converter（光信号转换器）介绍: 将接收到的光信号转换为电信号以供进一步处理MIMO:含义: Multiple Input Multiple Output（多输入多输出）介绍: 一种使用多个发射器和接收器来提高通信系统容量和可靠性的技术Hardware Pre-Equalizer:含义: 硬件预均衡器介绍: 在硬件层面上对信号进行预处理的设备，以减少传输过程中的失真Si-Based LED:含义: 硅基发光二极管介绍: 使用硅材料制造的LED，具有较高的效率和稳定性LED Array:含

无线光通信 · 03-18

EAWC | Listening, note-taking and summary

Listening and note-takingTips for note-taking:Don't take notes just for taking notes. Take it in an valuable and worthy way.Concentrate on important words (usually nouns, verbs, etc.) that give important information to you.Omit unimportant words.Have a consistent system for punctuation and abbreviation that will make sense to you. (It's unnecessary to make sense for others)Make the best of abbreviations, symbols and shapes.Summary writingGist: the main or essential part Summary: a comprehensive

English for academic writing and communication · 2024-11-22

EAWC | Seminar discussion and presentation

Discussion skillsEffective discussion should be:Be an attentive audienceA discussion should have a conclusion (decisions), otherwise it is an ineffective discussionTips for participating a discussion:For freshmen:ask a question so that the speaker can clarify or elaborate on a point that you don't understandask cause-and-effectFor junior students:explain that you find the speaker's opinions or points interesting and describe whybased on what the speaker had said and extend his opinion / pointspa

English for academic writing and communication · 2024-11-15

EAWC | Results, discussion, conclusion & poster presentation

Final part of paper writingSection of resultsIn this section, specific data of the work and detailed analysis of the data should be fully presented.Three moves to write results part:Provide preparatory informationDescribe the data in figures and tablesReport the results based on the dataWriting requirements for results:any data given in this section must be meaningfulpresentation of the data should be short without verbiage and be crystal claritythis section should also be well-written and shoul

English for academic writing and communication · 2024-11-08

DCN | Semi-Markovian system

M/G/1 queuing systemG means general distribution / more general situation. In this case, service time of the server has a general distribution with mean $X=E[x ]=1/\mu$ and standard deviation $\sigma_x$, where $mu$ is the mean service rate (services per second, etc.)Mean waiting time for a service request can be described by P-K formula: $$W=\frac{\lambda E[x^2]}{2(1-\rho)} $$ Using Little's Law, we can obtain the mean number of service requests in the buffer: $$N_Q=\lambda W=\frac{\lambda^2 E[x

Data communication networks · 2024-11-05

EAWC | Introduction, methods & editing

How to write a good introductionImportancemost read partdetermine the attitude of readerthe most dedicate partThe earlier you write the introduction part, the more you have to polish in the end. It's greatly suggested writing the introduction part after you finish the main body or at least the draft of your whole paper.Writing grammarTensePresent Simple/Present Continuous: this pair is used to state accepted facts and truths.Past Simple/Present Perfect: this pair is used to discuss the knowledge

English for academic writing and communication · 2024-11-01