Programmer Group

Portal: QAQQAQ   Topic: Give you N points on the coordinate axis. Ask you the number of different point sets divided by one horizontal line and two vertical lines (excluding empty sets).   Thought: When I don't think clearly, I think it's a water problem: for y-axis sort, then scan from bottom to top to see the number of X different s, ans+ ...

1.Ioc (inversion of control) controls inversion (an idea). IoC is an idea. Before that, the creation of objects used in programs must be completed by programmers. IoC entrusts the creation, preservation and management of objects (life cycle) to Spring, so Spring is also equivalent to a container (object of objects stored), which is the process ...

The pit of PHP in_array ps: Should be the pit of weakly typed languages php document As the name implies, in_array is to find out whether a value is in an array. problem Assuming the scene of the accident The test code for an sql injection is as follows: $type = $_GET['type']; $types = [2,3,4,5,6]; if(!in_array($type, $types)) { throw new Para ...

Demand point In many scenarios, the information can not be easily modified. When modifying, it needs either permission or approval. However, in either way, the data before and after modification needs to be kept "background". That is to say, the key information is modified with modification records. Generally, modification records re ...

Now there is a group of tasks, each task has a start and end time and a priority, give you the start and end time and priority of all tasks, ask you at a certain point in time the minimum priority k priority sum.   Ordinary chair tree is a single point modified interval query.   We can use difference array to do prefix sum of interval query ...

Since the widget document was updated, automatic authorization has ceased to exist. Current authorization is achieved through button. Specific knowledge points can refer to the official documentation of the applet. Here is a small demo I made (enter the home page, pop-up boxes, pop-up boxes are a UI component written by myself), nonsense, dire ...

The essence of mask: The image of the original image and the mask mask are processed and transported, and the result image is obtained. What is the operation of maps and masks? In fact, each pixel in the image and each corresponding pixel in the mask are processed and operated. For example: 1 & 1 = 1; 1 & 0 = 0; For example, a 3* ...

Realm Profile: Again, data domains, Shiro, and connectors for secure data are like jdbc connecting to databases; getting information about authentication and authorization through realm realm effect: Shiro retrieves security data from Realm The default home realm: idae looks at realm inheritance relationships with default implementations a ...

According to the requirement of the project, the data should be returned according to the background interface, and the form content should be added dynamically.   Description: This component is based on Ant Design of Vue   Six form controls are currently supported: Text Input, Text Area, Select Input, Select Multiple, Data Picker, and Data ...

"ZJOI2014" Galaxy Survey The core of this topic is to quickly find the linear hypothesis repulsion of XPs. The square of the distance from point ((x1,y1)) to line (y=kx+b) is ( displaystyle {(kx1+b-y1)^2}\over {k^2+1}. Then the relative exclusion of XPs is ( displaystyle sum {i points on the path} {(kx_i + b-y_i) ^ 2} over {k ^ 2 + ...