• Linux learning notes task planning crontab


    A series of articles: Linux learning notes — File packaging and decompression Linux learning notes task planning crontab Task plan crontab Crontab command is commonly used in UNIX and UNIX like operating systems (Linux belongs to UNIX like operating system), which is used to set instructions to be executed periodically. If we need to clean […]

  • Algorithm related problems


    1. Permutation problem You need to use Python’s itertools module import itertools a=[1,2,3] #Take, arrange (mathematical formula: A32) for i in itertools.permutations (a, 2): # 2 is taken twice. A can be a string or a list print(i) ”’ (1, 2) (1, 3) (2, 1) (2, 3) (3, 1) (3, 2) ”’ #Combination (mathematical formula: […]

  • CSS: the fun of focus within


    I believe some people have seen this picture of station B entering the password to cover their eyesHere we play with: focus within The layout is like thisThere is a CTN outside that can be ignored, just a fixed position in the middleThe image of “Suo” in xpassword is hidden before clickingThe “R6m” after xpassword […]

  • Layout of Android (how to realize the layout of hollow circle effect)


    Layer list: in short, layer list means layer list, which is used to create layer drawable. Layer drawable is a kind of drawableresource. Therefore, layer list creates “layer list”, which is a drawable graphic

  • Embedded runtime is always used for dependency resolution


    This sentence will be prompted when eclipse Luna configures Maven installation.Eclipse uses built-in when running some tasks. If you want to use external projects, you need to display and specify “run as > Maven install”`Translating to English, it means that Eclipse will continue to employ its internal Maven instance in order to perform some tasks. […]

  • Scope in Maven dependency


    The function of scope element: controls the scope of the dependency element. Generally speaking, it is to control the range in which jar packages are loaded and used.The specific meaning of scope is as follows: Compile (default) Meaning: compile is the default value. If the scope value is not specified, the default value of the […]

  • Common instructions of nginx


    Recently, nginx is often used, so I want to take a look at the common instructions of the system HttpCore instruction set server_name Meaning: set the name of the virtual server, the first name will become the name of the main server; the server name can use * instead of the first or last part […]

  • Service Custom index in kubernetes


    Prometheus indicator type Counter CounterType represents an indicator of monotonically increasing sample data, i.e. only increase but not decrease, unless the monitoring system is reset. For example, promql can be used to analyze the change rate of the main function generated by HTTP. Get the growth rate of HTTP requests rate(http_requests_total[5m]) HTTP request address of […]

  • [golang] pprof memory index


    Recently, some go services in the group have encountered memory related problems, so I took time to look at the meaning of the go pprof memory index today to prepare for subsequent problems.The content mainly comes from the comments on these fields in the go code and my own understanding. If you understand something wrong, […]

  • Front end knowledge system


    I have been on the road of the front end for more than three years. Because I am self-taught, I learned a lot of things, such as HTML, CSS and JavaScript at the beginning. I learned them seven or eight at the first time. I really can’t remember them. Later, I learned them again a […]

  • After git commit, you want to cancel the commit


    Solution: git reset — soft head^Reprinted at( https://blog.csdn.net/w958796… After writing the code, we usually do this Git add. / / add all files Git commit – M “this function is all completed” After executing the commit, what should I do if I want to withdraw the commit? This cold sauce: git reset –soft HEAD^ This […]

  • Ubuntu user management


    New users adduserCommand to add a new user This command is easy to understand, as the name implies: add means add, user means user, all in all, add user. The usage is very simple. The user name to be added is written directly after the command $ adduser frank Just enter the password, then enter […]