Tag:State value

  • The DFS solution of leetcode 123, 188 stock trading problem template

    Time:2021-4-29

    The common point of these two problems is that there is a limit on the number of transactions, that is to say, there are two states changing: I (the current date is the index of the array) and K. Here, the state of DFS is found, that is, the parameter of DFS function:function dfs (i,k){} […]

  • Tkinter (24) check button unit ttk.Checkbutton

    Time:2021-1-15

    Creation of TTK check button part and its options w = ttk.Checkbutton(parent, option=value, …) option explain class_ Component classification name cannot be changed after creation command The function called by the component compound The position of the image relative to the string, tk.TOP/BOTTOM/LEFT/RIGHT , set as picture priority, no string cursor The mouse that appears […]

  • Vue ssr

    Time:2021-1-12

    Component lifecycle hook function Should be avoided inbeforeCreateandcreatedCode that has global side effects during the lifecycle.For example:In whichsetIntervalSet timer. In the client side only code, we can set a timer, and thenbeforeDestroyordestroyedIt is destroyed at the end of its life cycle.However, since the destroy hook function is not called during SSR, the timer will remain […]

  • Redis concurrent competitive key solution details

    Time:2020-3-28

    Redis high concurrency The high performance of redis cache is obvious to all, and the application scenarios are also very extensive. But in the high concurrency scenario, there will also be problems: Today, we will talk about the problem of redis concurrent competition. Here, concurrency refers to the concurrency problem caused by multiple redis clients […]

  • How to query the result by another time field in the case of grouping?

    Time:2020-3-28

    If there is such a table: The script is as follows: DROP TABLE IF EXISTS `jl_site_operation`;CREATE TABLE `jl_site_operation` ( `id` int(11) NOT NULL AUTO_INCREMENT,`Site [ID ` int (11) default null comment ‘station ID’,`Param_id ` int (11) default null comment ‘parameter ID (associated jl_parameter_config table ID)’,`Param_value ` varchar (255) default null comment ‘the value corresponding to […]

  • IFLYTEK voice chip xfs5152ce, sharing some holes encountered

    Time:2019-10-20

    First, the I2C address of the chip manual is write address, which is 8-bit. The real address is 7-bit address, which should be 0x40. The lowest bit is read-write bit. Read set 1, which is 0x81, write set 0, which is 0x80. If I simulate I2C, it doesn’t matter. The most important thing is that […]