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Title, I'm a little confused, who can say it carefully: 1, the difference between psr-0 and psr-4 in composer; 2, the difference between the psr-0 norm and the psr-4 norm; 3, composer and Php-fig, who indulge who. Reply content: Title, I'm a little confused, who can say it carefully:1, the difference between psr-

As the question, I am engaged in a little mixed, who can be careful to talk about: 1, composer psr-0 and psr-4 In the difference; 2, psr-0 specifications and psr-4 specifications of the difference; 3. composer and php-fig. For example, I am a bit confused. Who can tell me carefully: 1. The difference between psr-

become more and more as the amount of data increases, such as a database called MyDB in the system, then the files that make up the MyDB database will have mydb.ns,mydb.0 , Mydb.1 and so on.Mydb.ns records the namespace of the database JSON object (namespace abbreviation for NS), which is the namespace within the database collection. mydb.0 and Mydb.1 are the space for objects that hold the database mydb,

two number and stored in the array B, to sort a (the original array) and B array, to determine a[i=0]+b[j= (n (n-1))]=0?, if three number 22 and equal to 0, then to the result array, (guaranteed output results are not duplicated), The final output result set. See the code, write a bit messy, hope forgive me!AC Code:Four-digit and whether 0http://www.51nod.com/on

51nod 1090 3 count and 0 amp; 51nod 1267 4 count and 0 (marked as binary) Question meaning: The sum of 3 is 0: An unordered array with the length of N is given. The elements in the array are integers, positive and negative values include 0, and they are not equal to each o

The sixth chapter recommends 4 hours of study time 10 chaptersHow to learn: read it in detail and implement the relevant code manuallyLearning Goals : This tutorial will teach you to install node, build servers, Express, MySQL, MongoDB, write background business logic, write interfaces, and finally complete a complete project backstage, a total of 10 days is expected.Database Database management struc

The seventh chapter recommends 4 hours of study time 10 chaptersHow to learn: read it in detail and implement the relevant code manuallyLearning Goals : This tutorial will teach you to install node, build servers, Express, MySQL, MongoDB, write background business logic, write interfaces, and finally complete a complete project backstage, a total of 10 days is expected.node. js Operation MangodbCreate a fol

How to learn: read it in detail and implement the relevant code manuallyLearning Goals : This tutorial will teach you to install node, build servers, Express, MySQL, MongoDB, write background business logic, write interfaces, and finally complete a complete project backstage, a total of 10 days is expected.node. js Operation MangodbCreate a folder for placing today's files, NPM init initializes, and creates demo1.js for writing node codeInstall the

-- logpath/data/logs/mongodb/shard22.log -- logappend -- port = 27018-replSet shard_1905_02-maxConns = 2000-oplogSize 100-forkThe above operations on the 192.168.3.201 server are as follows:/Usr/local/mongodb/bin/mongod -- dbpath =/data/mongodb/shard23 -- logpath/data/logs/mongodb/shard23.log -- logappend -- port = 27

loop output: forEach () must define a function for each cursor element to call. > Db. things. find (). forEach (printjson ); {"_ Id": ObjectId ("4c2209f9f3924d31102bd84a"), "name": "mongo "} {"_ Id": ObjectId ("4c2209fef3924d31102bd84b"), "x": 3} {"_ Id": ObjectId ("4c220a42f3924d31102bd856"), "x": 4, "j": 1} {"_ Id": ObjectId ("4c220a42f3924d31102bd857"), "x": 4, "j": 2} {"_ Id": ObjectId ("4c220a42f3924d

Summary: Meet halfway. Compare map, quick row + binary search, hash efficiency.n is the level of 4000, the direct O (n^4) is definitely super, so the Midway encounter method, O (n^2) time enumeration where two and, O (n^2) time enumerates the other two and the opposite number, and then O (LOGN) The time the query exists.First try the map, decisive tle//TLE#include #include#includeusing namespacestd;Const intMAXN =4001;intdata[

ModeMongoDB learning notes (4) describe the data relationship using the document structure of MongoDBMongoDB Study Notes (5) MongoDB File Access OperationsMongoDB Study Notes (6) MongoDB index usage and Efficiency Analysis 1. Set Operations that contain sub-Documents In such an application scenario, a website provides the member login function. Users must regis

The Find () function in the MongoDB returns a cursor that enables the client to effectively control the query results by setting some settings on the cursor, such as restricting the number of results obtained by the query, skipping partial results, or pressing any key to the result set. We used to operate in the shell, using the Find () function directly, without using its return value, such as: > for (var i=0