Programming VIP

In the process of data report and background management system development, we often encounter the operation of summing and filtering the data we get. In fact, it is not difficult to realize them, but if multiple pages need to do these operations, it is troublesome to write a little bit more. When some code repetitio ...

Preface The charge system of the computer room has entered the registration window. I feel that the computer room is the same as many places of the students, but because the computer room is completed by myself, and the help from the outside is less, I have to sort out the logic by myself and design the code by myself (most of them are to fin ...

Iterator interface, translated into Chinese is iterator The concept of iterator is generally explained as follows: There are many collections in java. There are various internal storage methods and different ways to get them. Can there be a general way to get them? This is similar to for loop traversal, General method of obtaining: before takin ...

1.find command Command format: find directory condition value 1.find -name find /etc/ -name passwd ##Find the file named passwd under / etc 2.find -user -group -a -o -not find /mnt -group root find /mnt -user westos find /mnt -group root -user student ##and find /mnt -group root -a -user student ##Both c ...

To find the K-th largest number, we often think of the chairman tree, but the chairman tree code is complex and the operation is complex. If we simply find the K-th-largest number in the sequence, then it seems to have advantages and disadvantages, like ACdream 1099 This problem is to find the number with the largest K in the sequence, and if ...

1, Table structure CREATE TABLE `visitor_log` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `uicode` varchar(32) NOT NULL, `actcode` varchar(10) DEFAULT '', `F` varchar(30) DEFAULT '', `uid` bigint(20) NOT NULL, `element` varchar(32) DEFAULT '', `create_time` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00 ...

7, Knowledge and practice of if structure conditional sentence (1) if conditional single and double branch syntax 1. Single branch if condition then instructions fi 2. Bifurcate if condition then instructions else Instruction set 2 fi (2) if conditional multi branch statement 1. Structure of statement if condition 1 then ...

This paper studies the creation, expansion and implementation of deep copy of golang slice from the perspective of source code. Internal data structure slice has only three fields, among which array is the part to save data, len field is the length and cap is the capacity. type slice struct { array unsafe.Pointer // Data section len in ...

  1, Preparations 1 download and install python2 download and install VS code EditorWhen installing, please check add to path   3 install pygame moduleNote: many people will encounter various problems in the process of learning python, and no one will help answer the questions. For this reason, I have built a python full stack fr ...

Preface What will the following program output? package mainimport "fmt"func f(s []string, level int) {        if level > 5 {               return        }        s = append(s, fmt.Sprint(level))        f(s, level+1)        fmt.Println("level:", level, "slice:", s)}func main() {        f(nil, 0)} Its output is: level: 5 slice: [0 1 2 3 4  ...