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ARTS ARTS is an activity launched by Chen Hao in the geek time column, aiming to stick to learning through sharing. Each person writes an ARTS every week: Algorithm is an Algorithm problem, Review is to read an English article, technology / tips is to Share a small technology, and Share is to Share a point of view. This week This week's ARTS yo ...

explain: Ten sorting algorithms are implemented in Python. There is only a simple explanation and no detailed introduction of the algorithm. Related terms: Stable sorting: if a is in front of B, and a==b, a is still in front of B after sorting, it is a stable sorting. Unstable sorting: if a is originally in front of b, and a==b, and a may not b ...

==> Learning summary (continuous update) ==> Build back-end infrastructure series from scratch (I) -- background introduction Summary: Part I A simple lockless thread pool is realized, novelette This paper focuses on the analysis of java thread pool source code. 1, Basic conceptsIn fact, to under ...

Point Cloud Filtering wave filtering When acquiring point cloud data, due to the impact of equipment accuracy, operator experience, environmental factors and other factors, some noise points (that is, points we can't use) are inevitable in point cloud data. We need to remove these points when proces ...

catalog 1 project construction 1.1 new project and operation 1.2 configure basic appearance according to project effect 2. Frame up 2.1 configure tabbar 3 get data from the background 3.1 package request component 3.2 build background application 4 home page 4.1 configure basic data of home page ...

rip and ospf routing protocol rip routing protocol brief introduction Information protocol historical information principle edition RIPv1 RIPv2 The difference between rip and rip2 rip-1 rip-2 RIPng Protocol layering Frequently asked questions ospf routing protocol summary Implementation proce ...

12.3 Based on the principal component analysis of the scores of 50 students in the table below, how many comprehensive variables can be selected to represent the scores of these students in 6 courses? The data are as follows: 1. Data import and data standardization > data=read.csv('D:/R languaga_ma ...

Slow Query Log Understanding slow queries mysql's slow query is a type of log record provided by mysql that records statements whose execution time exceeds the set threshold.This time-out is configurable, and the default time-out is 10s, which is then written to the log.Then combined with explain to ...

A-Chemistry Chemistry is amazing. Here are the alkyl groups. Suppose, as shown above, this alkyl group has six atoms and five chemical bonds, six atoms labeled 1-6, and then a pair of numbers a and b denotes that there is a chemical bond between atom A and atom b.This allows a description of an alkyl ...

Subquery 1. What is a subquery -- Requirements: Query who is in the development department select * from emp; -- Query by two statements select id from dept where name='Development Department' ; select * from emp where dept_id = 1; -- Use subqueries select * from emp where dept_id = (select id from dept where name='Marketing Department'); ...