是否 Olymp Trade 有移動應用程序嗎?


All children deserve protection from online sexual abuse

We work to stop the repeated victimisation of people abused in childhood, and make the internet a safer place, by identifying & removing global online child sexual abuse imagery.

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IWF Annual Report 2021

In 2021, we assessed a webpage every one-and-a-half minutes. Every two minutes, that webpage showed a child being sexually abused.

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IWF's 25th anniversary

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See more of the data and trends from 2021 in our Annual Report.

IntelliGrade: Ground-breaking new tech from IWF

IntelliGrade, from the Internet Watch Foundation, is helping companies and law enforcement bodies to fight back against criminals who trade, store and upload images and videos showing the sexual abuse of children.

It's is a powerful new tool that enables our analysts to accurately grade child sexual abuse images and videos, and create hashes (digital fingerprints) that are compatible with child sexual abuse laws and classifications in the UK, US, Canada, Australia, New Zealand and the Interpol Baseline standard.

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IWF CEO, Susie Hargreaves OBE, on Times Radio

IWF CEO, Susie Hargreaves OBE, on Times Radio

Susie speaks to Aasmah Mir about the increase in self-generated child sexual abuse online amongst 7-to-10 year olds

3 Ways you can help to protect children online

3 Ways you can help to protect children 是否 Olymp Trade 有移動應用程序嗎? online

Natterhub's Caroline Allams offers practical tips for parents and carers

20,000 reports of coerced ‘self-generated’ sexual abuse imagery seen in first half of 2022 show 7- to 10-year-olds

20,000 reports of coerced ‘self-generated’ sexual abuse imagery seen in first half of 2022 show 7- to 10-year-olds

IWF CEO calls it a social and digital emergency requiring a sustained national prevention effort.

Apple should scan iPhones for child abuse images, says scanning technology inventor

Apple should scan iPhones for child abuse images, says scanning technology inventor

Prof Hany Farid says all online services should adopt idea backed by GCHQ and National Cybersecurity Centre

Encryption Vs. Privacy: In Conversation with Professor Hany Farid

Encryption Vs. Privacy: In Conversation with Professor Hany Farid

Speaking exclusively to the IWF as part of its new 是否 Olymp Trade 有移動應用程序嗎? podcast series, Prof Farid, said children are facing dangers online, and that politicians need to step in to make sure tech companies are incentivised to bring in better child protection measures.

IWF data fuels report aimed at ‘turning tide of online child sexual abuse’

IWF data fuels report aimed at ‘turning tide of online child sexual abuse’

A new report by an independent think tank looks at what can be done by police and government to help “turn the tide of online child sexual abuse”.

The IWF combines the technical know-how with a deep understanding of the human cost of this awful crime. The organisation's work creates scale and impact to tackle this issue, and Google is proud to work so closely with the IWF.

CodeForce#1625B Elementary Particles解题笔记

McDuck_Spirit 于 2022-03-06 22:30:02 发布 167 收藏

B. Elementary Particles

time limit per test

memory limit per test

Martians are actively engaged in interplanetary trade. Olymp City, the Martian city known for its spaceport, has become a place where goods from all the corners of our Galaxy come. To deliver even more freight from faraway planets, Martians need fast spaceships.

A group of scientists conducts experiments to build a fast engine for the new spaceship. In the current experiment, there are nn elementary particles, the ii-th of them has type aiai.

Denote a subsegment of the particle sequence (a1,a2,…,ana1,a2,…,an) as a sequence (al,al+1,…,aral,al+1,…,ar) for some left bound ll and right bound rr (1≤l≤r≤n1≤l≤r≤n). For instance, the sequence (1 4 2 8 5 7)(1 4 2 8 5 7) for l=2l=2 and r=4r=4 has the sequence (4 2 8)(4 2 8) as a subsegment. Two subsegments are considered different if at least one bound of those subsegments differs.

Note that the subsegments can be equal as sequences but still considered different. For example, consider the 是否 Olymp Trade 有移動應用程序嗎? sequence (1 1 1 1 1)(1 1 1 1 1) and two of its subsegments: one with l=1l=1 and r=3r=3 and another with l=2l=2 and r=4r=4. Both subsegments are equal to (1 1 1)(1 1 1), but still considered different, as their left and right bounds differ.

The scientists want to conduct a reaction to get two different subsegments of the same length. Denote this length kk. The resulting pair of subsegments must be harmonious, i. e. for some ii (1≤i≤k1≤i≤k) it must be true that the types of particles on the ii-th position are the same for these two subsegments. For example, the pair (1 7 3)(1 7 3) and (4 7 8)(4 7 8) is harmonious, as both subsegments have 77 on the second position. The pair (1 2 3)(是否 Olymp Trade 有移動應用程序嗎? 1 2 3) and (3 1 2)(3 1 2) is not harmonious.

The longer are harmonious subsegments, the more chances for the scientists to design a fast engine. So, 是否 Olymp Trade 有移動應用程序嗎? they asked you to calculate the maximal possible length of harmonious pair made of different subsegments.

The first line contains an integer tt (1≤t≤1001≤t≤100) — the number of test cases. The following are descriptions of the test cases.

The first line contains an integer nn (2≤n≤1500002≤n≤150000) — the amount of elementary particles in the sequence.

The second line contains nn integers aiai (1≤ai≤1500001≤ai≤150000) — types of elementary particles.

It is guaranteed that the sum of nn over all test cases does not exceed 3⋅1053⋅105.

For each test, print a single integer, maximal possible length of harmonious pair made of different subsegments. If such pair does not exist, print −1−1 instead.

The first test case is shown on the picture below:

As you can see from it, you may choose the subsegments (2 1 3 4)(2 1 3 4) and (3 1 5 2)(3 1 5 2), which are a harmonious pair. Their length is equal to 44, so the answer is 44.

In 是否 Olymp Trade 有移動應用程序嗎? the second test case, you need to take two subsegments: one with l=1l=1 and r=5r=5, and one with l=2l=2 and r=6r=6. It's not hard to observe that these segments are a harmonious pair and considered different even though they are both equal to (1 1 是否 Olymp Trade 有移動應用程序嗎? 1 1 1)(1 1 1 1 1).

In the third test case, you cannot 是否 Olymp Trade 有移動應用程序嗎? make a harmonious pair, so the answer is −1−1.




甚至是想罢工的一天!!!相关知识见,感觉比较容易入手1.数据链路层的定位与功能 水平传送P70 71图数据链路层不必考虑物理层的比特传输细节,只需要考虑数据链路层如何封装: 添加首部(SOH)与尾部(EOT)实现帧定界MUT = 数据部分最大长度!= 帧最大长度字节填充(转义字符)与比特填充CRC(循环冗余检验)消除比特差错FCS:帧检验序列,冗余码 2^nM+FCS n+1 = |P|若 R = 0,则接受若R!= 0 ,则判断为差错,丢弃。


调制:基带调制(编码, 变换波形, 数字->数字,不归零,归零,曼彻斯特,差分曼彻斯特)与带通调制(载波),改变频率范围->模拟,调幅,调相,调频)5.假定某信道受奈式准则限制的最高码元速率为20000码元/秒,如果采用振幅调制,把码元的振幅划分为16个不同等级来传送,那么可以获得多高的数据率(bit/s)?中,码元的传输的效率是有上限的,传输速率超过此上限,就会出现严重的码间串扰问题,使接收端对码元的判决(即识别)成为不可能。B内积:(是否 Olymp Trade 有移動應用程序嗎? +1 -1 -3 -1 -1 -3 +1 -1)/8 = -1。


相关知识见,感觉比较容易入手《计算机网络》(谢希仁)内容总结 | JavaGuide1.网络的概念网络:主机、结点、链路internet 互连网:网络+路由器+链路,通用名词Internet互联网:最大的开放的由多个网络连接而成的特定互连网,采用TCP/IP协议簇2.是否 Olymp Trade 有移動應用程序嗎? 互联网的组成C/S、P2P、B/S(C/S的特例)3.互联网发展的三阶段1)单个网络ARPANET向互连网发展2)建成三级结构的互联网3)逐渐形成多层次的ISP结构的互联网


1、函数依赖的定义:设有关系模式R(A1,A2,. An)或简记为R(U),X,Y是U的子集,r是R的任一具体关系,如果对r的任意两个元组t1,t2,由t1[X]=t2[X]导致t1[Y]=t2[Y],则称X函数决定Y,或Y函数依赖于X,记为X→Y。3)假设关系模式R如下:R ( Sno,Sdept,Sloc,Cno,Grade ) 其中Sno为学号,Sdept为学生所在系,Sloc为学生的住处,Cno为学生所选修课程号,Grade为成绩。关系模式是用来定义关系的,表的结构,一个关系数据库包含一组关系。.




优化:πCNAME,TEACHER(πCNAME,TEACHER(C)|X|(πS#,C#(SC)|X|πS#(σSEX='女'(S))))πCNAME,TEACHER(σSEX='女'(S|X|SC|X|C))1)试写出该查询的关系代数表达式,试写出查询优化的关系代数表达式;查询检查 是否 Olymp Trade 有移動應用程序嗎? (语义分析,符号名转换,安全性检查,完整性初步检查)3)使用优化算法,对语法树进行优化,并画出优化后的语法树。2)画出该查询初始的关系代数表达式的语法树;查询分析 (语法分析,词法分析)查询优化(代数优化,物理优化).



视图是一张虚表,视图中的数据并不实际存储,定义保存在数据字典中,为了使通过视图插入新行时,元组满足视图的定义条件,定义视图时要加上WITH CHECK OPTION子句。更新视图要转换为对基本表的更新,类似视图的消解,并不是所有视图都是可更新的,但一般行列子集视图是可更新的。CREATE VIEW [([,[. ]])][NOT] LIKE '' [ESCAPE'']VALUES('99001','李明', '男', 22,'经管系').



数据库系统阶段:1)数据结构化 2)有较高的数据独立性 3)共享性高,冗余度低,易扩充 4) 系统提供了四个方面的数据控制功能:数据库的恢复、并发控制、数据完整性和数据安全性。文件系统阶段:1)数据可以长期保存 2)数据在逻辑与物理结构上存在区别 3)文件组织呈现多样化 4)数据可重复使用 5)文件系统管理数据 6)数据共享性差,冗余度大 7)数据独立性差 8)数据不一致性 ,数据联系弱。数据描述的两种形式:物理描述(数据在存储设备上的存取方式)和逻辑描述(程序员或用户用以操作的数据形式)。.

第十届蓝桥杯国赛C/C++ 大学B组 试题C: 拼接

Codeforces Round #782 (Div. 2)B. Bit Flipping

#include #define inf 0x3f3f3f3f#define int long long#define PII pair#define rep(x, a, b) for(int x = a; x= a; x--)using namespace std;const int N =1e.

L2-035 完全二叉树的层序遍历 (25 分)

一个二叉树,如果每一个层的结点数都达到最大值,则这个二叉树就是完美二叉树。对于深度为D的,有N个结点的二叉树,若其结点对应于相同深度完美二叉树的层序遍历的前N个结点,这样的树就是完全二叉树。给定一棵完全二叉树的后序遍历,请你给出这棵树的层序遍历结果。输入格式:输入在第一行中给出正整数N(≤30),即树中结点个数。第二行给出后序遍历序列,为N个不超过 100 的正整数。同一行中所有数字都以空格分隔。输出格式:在一行中输出该树的层序遍历序列。所有数字都以 1 个空格分隔,.

L2-028 秀恩爱分得快 (25 分)

古人云:秀恩爱,分得快。互联网上每天都有大量人发布大量照片,我们通过分析这些照片,可以分析人与人之间的亲密度。如果一张照片上出现了 K 个人,这些人两两间的亲密度就被定义为 1/K。任意两个人如果同时出现在若干张照片里,他们之间的亲密度就是所有这些同框照片对应的亲密度之和。下面给定一批照片,请你分析一对给定的情侣,看看他们分别有没有亲密度更高的异性朋友?输入格式:输入在第一行给出 2 个正整数:N(不超过1000,为总人数——简单起见,我们把所有人从 0 到 N-1 编号。为了区分性别,我们用.


L2-011 玩转二叉树 (25 分)给定一棵二叉树的中序遍历和前序遍历,请你先将树做个镜面反转,再输出反转后的层序遍历的序列。所谓镜面反转,是指将所有非叶结点的左右孩子对换。这里假设键值都是互不相等的正整数。输入格式:输入第一行给出一个正整数N(≤30),是二叉树中结点的个数。第二行给出其中序遍历序列。第三行给出其前序遍历序列。数字间以空格分隔。输出格式:在一行中输出该树反转后的层序遍历的序列。数字间以1个空格分隔,行首尾不得有多余空格。输入样例:71 2 3 4 5 6.是否 Olymp Trade 有移動應用程序嗎?


小明维护着一个程序员论坛。现在他收集了一份"点赞"日志,日志共有N行。其中每一行的格式是:ts id。表示在ts时刻编号id的帖子收到一个"赞"。现在小明想统计有哪些帖子曾经是"热帖"。如果一个帖子曾在任意一个长度为D的时间段内收到不少于K个赞,小明就认为这个帖子曾是"热帖"。具体来说,如果存在某个时刻T满足该帖在[T, T+D)这段时间内(注意是左闭右开区间)收到不少于K个赞,该帖就曾是"热帖"。给定日志,请你帮助小明统计出所有曾是"热帖"的帖子编号。输入格式第一行包含.


D. Spy-stringYou are givennnstringsa1,a2,…,ana1,a2,…,an: all of them have the same lengthmm. The strings consist of lowercase English letters.Find any stringssof lengthmmsuch that each of the givennnstrings differs fromssin at most one pos.


题目描述给定三个整数数组A = [A1, A2, . AN],是否 Olymp Trade 有移動應用程序嗎? B = [B1, B2, . BN],C = [C1, C2, . CN],请你统计有多少个三元组(i, j, k) 满足:1. 1

Codeforces Round #778——C. Alice and the Cake

Alice has a cake, and she is going to cut it. She will perform the following operationn−1n−1times: choose a piece of the cake (initially, the cake is all one piece) with weightw≥2w≥2and cut it into two smaller pieces of weight⌊w2⌋⌊w2⌋and⌈w2⌉⌈w2⌉(⌊.









Codeforces Round #747 (Div. 2)B. Special Numbers

Theofanis really likes sequences of positive integers, thus his teacher (Yeltsa Kcir) gave him a problem about a sequence that consists of only special numbers.Let’s call a positive number special if it can be written as a sum of different non-negative pow

解决:python爬虫运行报错——AttributeError: ‘WebDriver‘ object has no attribute ‘find_elements_by_class_name‘




A. Consecutive Sum Riddle( Codeforces Round #747 (Div. 2))

Theofanis has a riddle for you and if you manage to solve it, he will give you a Cypriot snack halloumi for free (Cypriot cheese).You are given an integer nn. You need to find two integers ll and rr such that −1018≤l


一、域名系统DNS1.1概念是什么DNS(Domain Name System),是互联网用使用的命名系统,用来把便于人们使用的机器名字转换为IP地址。(物理地址为MAC地址)为什么对于用户:能够把互联网上的主机名字转换为IP地址,便于用户记忆。对于机器:处理IP地址更容易,IP地址是固定的32位。怎么用的域名系统DNS是一个联机分布式数据库系统。1.2怎么存储的层次树状结构。任何一个连接在互联网上的主机或路由器,都有一个唯一的层次结构的名字,即域名。怎么


L2-042 老板的作息表(25分) 2022天梯赛c++

新浪微博上有人发了某老板的作息时间表,表示其每天 4:30 就起床了。但立刻有眼尖的网友问:这时间表不完整啊,早上九点到下午一点干啥了?本题就请你编写程序,检查任意一张时间表,找出其中没写出来的时间段。输入格式:输入第一行给出一个正整数 N,为作息表上列出的时间段的个数。随后 N 行,每行给出一个时间段,格式为:hh:mm:ss - hh:mm:ss其中 hh、mm、ss 分别是两位数表示的小时、分钟、秒。第一个时间是开始时间,第二个是结束时间。题目保证所有时间都在一天之内(即从 是否 Olymp Trade 有移動應用程序嗎? 00:00:0.

L1-088 静静的推荐(2022天梯赛c++)

今年一点也没有重视,开学后,或者甚至是寒假后就没有好好写过题,松懈太多,没有手感还是不行,太生疏了。一手好牌被自己打的稀烂。现在好好写写,希望期末的校赛好好打。天梯赛结束后,某企业的人力资源部希望组委会能推荐一批优秀的学生,这个整理推荐名单的任务就由静静姐负责。企业接受推荐的流程是这样的:只考虑得分不低于 175 分的学生; 一共接受K批次的推荐名单; 同一批推荐名单上的学生的成绩原则上应严格递增; 如果有的学生天梯赛成绩虽然与前一个人相同,但其参加过 PAT 考试,且成绩达到了该企业..

L1-086 斯德哥尔摩火车上的题 c++

上图是新浪微博上的一则趣闻,是瑞典斯德哥尔摩火车上的一道题,看上去是段伪代码:s = ‘’a = ‘1112031584’for (i = 1; i < length(a); i++) >goto_url(‘www.multisoft.se/’ + s)是否 Olymp Trade 有移動應用程序嗎? 其中字符串的 + 操作是连接两个字符串的意思。所以这道题其实是让大家访问网站 www.multisoft.se/112358(.




试题 算法训练 搬走要石

资源限制内存限制:256.0MB C/C++时间限制:1.0s Java时间限制:3.0s Python时间限制:5.0s问题描述 住在有顶天的天人Tensi对自己的住处很不满。终于有一天她决定把门前碍眼的要石通通丢掉(怒扔要石)。控制要石自然是很容易的事,不过也会消耗灵力。假设搬走一块质量为1的要石会消耗1点灵力,而且由于要石都是连着放置的缘故所以每次除了搬走一颗,也可以搬走连续的任意数量的要石,自然质量是算在一起的。现在Tensi准备最多使用M次灵力,但是她太懒……所以每次只会使用同