Tag:Overall situation

  • Leetcode 1014. Implementation of the best sightseeing combination in Python


    Title Requirements: Thinking: The score is a [i] + a [J] + I – J, which can be divided into (a [i] + I) and (a [J] – J, and the highest score is the sum of the two So traverse the array and maintain two values, one is the maximum value of a [i] […]

  • The principle of global dictionary for exact de duplication in Apache kylin 4.0


    Explanation of global dictionary Why do you need a global dictionary In the field of OLAP data analysis, count distinct is a very common requirement. According to the requirements of the result, it can be divided into approximate de duplication and accurate de duplication. In large-scale data sets, it is still very challenging to achieve […]

  • Introduction to namespace


    The function is to solve the conflict of referencing the same named class, function and constant in different files Let’s start with an example <?php namespace my\name; //Refer to the section defining a namespace class MyClass {} function myfunction() {} const MYCONST = 1; $a = new MyClass; $c = new \my\name\MyClass; //Refer to the […]

  • The difference of NPMI – S – D – G


    1)npm -i == npm install 2) Write to dependencies and publish to development environment npm install module_name –save == npm i module_name -S 3) Write devdependencies, production environment npm install module_name –save-dev == npm i module_name -D 4) Global installation npm i module_name -g || npm install module_name -g 5) Local installation (put package in. […]

  • How does Seata at ensure the consistency of distributed transactions


    Author: funkye GitHub ID: a364176773Source|Alibaba cloud official account Seata is an open source distributed transaction solution with 18100 + star and high community activity. It is committed to providing high-performance and easy-to-use distributed transaction services under the micro service architecture. This paper will analyze the implementation principle of Seata at, so that users can have […]

  • Apache shardingsphere integrates Seata at distributed transactions


    background knowledge Seata is a distributed transaction framework jointly built by Alibaba group and ant financial services. The current version includes at transaction and TCC transaction. The goal of at transaction is to provide incremental transaction acid semantics under the microservice architecture, so that users can use distributed transactions just like local transactions. The core […]

  • From scratch, initialize the project with elementui – Vue


    Project brief Xiaobian’s purpose of publishing this blog is to use Pan Jia Chen’s blogvue-element-admin、elunezAfter the big brother felt, according to the two big brother’s front-end template to write documents. This blog is expected to be published in 3 months, and the number of posts is expected to be 30-50. I hope you can collect, […]

  • [open source] hemo wexbox2 officially released


    WeexBox2 A simple and efficient solution for app hybrid development Write at the beginning Weexbox official QQ group number: 943913583 It’s been more than half a year since the release of weexbox1. We’ve been trying to add exciting features in the past half a year. Now it’s time to introduce weexbox2. Features of weexbox2 On […]

  • JavaScript — regular expression


    regular expression var expression = / pattern / flags; flags:Each regular expression can take one or more flags to indicate the behavior of the regular expression g: Represents a global pattern, that is, the pattern will be applied to all strings instead of stopping immediately when the first match is found. i: Indicates case insensitive […]

  • info There appears to be trouble with your network connection


    When using NPX create react app project name to create a new project, an error is reported; yarn add v1.22.4 info No lockfile found. [1/4] 🔍 Resolving packages… info There appears to be trouble with your network connection. Retrying… info There appears to be trouble with your network connection. Retrying… Solutions: Step 1: change Taobao […]

  • JS form verification (1): domain name verification instruction


    Implementation of angularjs app.directive(‘checkDomainCommon’, function () { return { restrict: ‘A’, require: ‘ngModel’, link(scope, ele, attrs, ctrl) { ctrl.$validators.checkDomainCommon = function (modelVal) { //Reg is the regularization of the domain name let reg =/^[a-zA-Z0-9][-a-zA-Z0-9]{0,62}(\.[a-zA-Z0-9][–a-zA-Z0-9]{0,62})+\.?/ if (attrs[‘required’] === undefined || attrs[‘required’] === false) { return true } else if(!modelVal){ return false; }else { //Add input type […]

  • Mini Redux implementation principle


    The article first appeared on my bloghttps://github.com/mcuking/bl… Please refer tohttps://github.com/mcuking/bl… First of all, we don’t think about react Redux, but how to realize the function of redux.Redux generates the global state tree store according to the reducer (the new global state is generated according to the old global state and action). Namely store = createStore(reducer) […]