• ## In depth understanding of data structure — binary tree (advanced part 1)

Time：2022-4-24

Series articles： In depth understanding of data structure — binary tree (advanced part 1) In depth understanding of data structure — binary tree (basic chapter) In the first part, the relative basic information of binary tree is sorted outIn depth understanding of data structure – binary tree (basic chapter) Next, we will explain the advanced […]

• ## Look at animation algorithms: balanced binary search tree AVL tree

Time：2022-4-22

brief introduction Balanced binary search tree is a special binary search tree. Why is there a balanced binary search tree? Consider the special case of binary search tree. If all nodes of a binary search tree are right nodes, the binary search tree will degenerate into a linked list. Thus, the time complexity of the […]

• ## Using machine learning to predict stock price

Time：2022-4-9

Stock price forecasts help determine the trend of stocks in the coming days or weeks, or at least show the trend. Stock prices depend on a number of factors, such as: Basic factors: revenue, profit, market share, potential growth prospects of the business External factors: pandemic, such as new crown, foreign exchange rate, oil price, […]

• ## He problem record – Combinatorial Mathematics

Time：2022-4-5

Binary number 2 ^ k Canon hard(worth doing!) analysis For condition “as”2kHexadecimal number, except the last digit,rEach bit of is strictly smaller than the one adjacent to its right“NamelyNumbers from left to right are in ascending order That is, find the combination number(since the scheme corresponding to the combination number is disordered, we can regard […]

Time：2022-3-31

Contents of this section 1. Introduction to demo 2. Analyze the size scale of greedy animation 3. Draw a circle 4. Realize the animation of opening and closing mouth 5. Small ball movement animation 1、 Introduction to demo 1. The effect is shown in the figure below. I cut three moments, but in fact, this […]

• ## 2021 national college student information security competition Anhui race – network attack and defense track – some WP crypto cross_ Fire

Time：2022-3-22

subject Cross_Fire.py from gmpy2 import * from libnum import s2n,n2s from Crypto.Util.number import * from flag import plaintext assert(len(plaintext)>128) e=65537 m=s2n(plaintext) p=getPrime(500) q=getPrime(1024) r=getPrime(1024) hint1=p*q*r hint2=next_prime(p)*next_prime(q)*next_prime(r) n=next_prime(123*p+456)*next_prime(233*q+233)*next_prime(666*r+666) c=pow(m,e,n) print(“hint1=”,hint1) print(“hint2=”,hint2) print(“e=”,e) print(“n=”,n) print(“c=”,c) ”’ hint1= 66597706438052968602907975635364474124624609040691375744383573309100970537667852695911406578339583406993354597653539587007399024156000284162006381513057917653763467490913961403796256103799712489840324677890516295291754752667080587689619591977796148937147026181153407872286012339573004262967216008992456987530280248046317633785368985937352761743401538167742790063446090181640923337990535120783172231525752911772643973809736013911022053243030289179238536988831429875919863032051710061637295482848897179403927441453047333367742504111531477527219109139209305898423562329209375385774722090035022238350104808001927840789351874748994613148197348389169808276135120368108948370654768586592518609889834086412071206692748953099899446867217942417300125520378227882738726940028929 hint2= 66597706438052968602907975635364474124624609040691375744383573309100970537667852695911406578339583406993354597653539587007399024156000284162006381519250037838090700817357286993539595751890863552857025186501118668940000586180857161834771657275281213521087010590085823066429019242511957345355841205805490396285530197202608369351669705515187871274740384884445010749950651326231261308185878145343225072286358030343013074077614396504748731540529394175170653286604110001303387433196918194353309815286558369700754725062771941489664316582212235229725924291159030267475029526286194732206037792356401019048507530494720324382797923052122766854647054667572207470351698834488250064200327557388850421313632751275068766021705342276955127790709872384961830995521889674866200643581197 e= 65537 n= 1271143363426234578109032622706784368982452702551117975547220359092039459949589311614475250751670324493441017909825758822014002389769016887770094631267325830636300148439767061540517538240094507617502786636783685853116121519909167755693185341466272016646232460012649033718198945340871434729792726475237884312244749128647675044166254114409979208613136490968091271215324179363007030770031883104198634577994666369930225951242263540549447415742095183638116238138212512007206154136596565735565134655180583298422538746349678634986942613303728294063886412713958813109459261894779056221585991240656450995515329105180293668452080201635903397760758605883754955173299769359099672851020901544947845931039456152020654355740641530636597180573996251235682717406311406638139251493213898068501 c= 1216485134271178449567116916754420573073303455397620989326464150108908572336526711707238151485187836142308657852844139181641136164876989706372528330194558764108985905734554870749686706876362171680539349216110583849976294434959121174943229853669205013854742739444539161076289486434305028669545715151531610132849739705231210851708893517910447015945450432744842995436173783966889593804335503774508824344205419870078981016701436069437155486571657204182510954434683255699530711440688659074538879785922444601494725802905576491078834520957416860895991743319707987718280613091465577249499325647665822748760483739502978877174961037108839466736686647462799492964587695553596641935803152814769663732674949417986994233658218593205643014847168221928973615157533648368075119704854913178864 ”’ 0x01 continued fraction Continued fraction script from Crypto.Util.number import * […]

• ## R data analysis: detailed introduction to the use of tableone package

Time：2022-3-21

Tableone is a package that helps us quickly generate the table1 table in an article. Generally speaking, the first table of an SCI article will give the baseline of the sample. Tableone is a package that can help us quickly summarize and describe the baseline variables of all samples. Today I will write tableone for […]

• ## R language Fama French (FF) three factor model and CAPM multi factor extended model analyze the visualization of portfolio risk / return in stock market

Time：2022-3-13

Original link:http://tecdat.cn/?p=24983 In this paper, we go beyond the simple linear regression of CAPM and explore the multifactor model of Fama French (FF) stock risk / return. FF model extends CAPM by regressing portfolio returns of several variables other than market returns. From the perspective of general data science, FF extends the simple linear regression […]

• ## [brick moving] practice of constructing prognostic signature

Time：2022-2-27

Cox regression model Write at the beginning:Sincerely recommend the Cox regression model R teaching video of uncoiling wheat!!! If you are still confused about Cox, click the link below! You can get super comfortable code in 15 minutes~[R operation of Cox regression: from single factor to multi factor at one gohttps://www.bilibili.com/video/av18918951/ 】 Final renderings According […]

• ## Understanding the data structure of map in go

Time：2022-2-27

This article wants to talk about the data structure of map in go and my understanding of it. If you are interested, you can continue to look at it Golang’s map uses a hash table as the underlying implementation. A hash table can have multiple hash table nodes, that is, buckets, and each bucket stores […]

• ## OO_ Unit1 summary

Time：2022-2-14

1、 Program structure analysis First job 1. Design conception and self-evaluation 　　The difficulty of the first operation is not too high. We only need to analyze the expression simply combined by constant and power function. Each item can be regarded as a fixed form of coef * x * * index. The term class containing […]

• ## R language uses additive multiple linear regression, random forest and elastic network model to predict abalone age and visualization

Time：2022-2-11

Original link: http://tecdat.cn/?p=24127 introduce Abalone is a kind of shellfish, which is regarded as a delicacy in many parts of the world. An excellent source of iron and pantothenic acid, it is a nutritious food resource and agriculture in Australia, the United States and East Asia. 100g abalone can provide more than 20% of the […]