bo3 tips

Some useful tips/small formulas/Xuan Xue optimization (fog, tips/Xuan Xue) 1. There are gcd (x1-x2, y1-y2)-1 points on the line segment (excluding the endpoint) consisting of (x1, y1) (x2, y2. 2. After two longlong values are multiplied, % of a number can be used in the following ways to avoid high precision: Ll mu (ll a, ll B) {ll r = 0; for (; B; a = (a 3. $ \ sum \ limits _ {I = 1} ^ n I ^ 2 = \

Python tips (keep updated) and python tips 1. view the class attributes and methods of import/export warehouse Python is a little inconvenient. Unlike C ++, when a type is specified, a "." error is prompted for the method or attribute it contains. Previously, it was solved by checking the official documents corresponding to the database. This time I found a new method help, which can list methods and attrib

SQL tips: WHERE 1 = 1, SQL tips Due to project requirements, you need to manually splice SQL statements (do not know what leaders think ......), And then return to the original age, append (SQL ). However, the subsequent query involves multiple dynamic conditions. if mybatis Is, You can directly splice dynamic SQL statements with the Later, a friend told me a way to easily solve this problem, that is, d

A few Ruby tips and Ruby tips Sequential call of code blocksCopy codeThe Code is as follows:Def touch_downYield [3, 7]Puts "touchdown! "EndTouch_down do | (first_down, second_down) |Puts "# {first_down} yards on the run"Puts "# {second_down} yards passed"End=> "3 yards on the run"=> "7 yards passed"=> "Touchdown! " It mainly refers to the use of array in block Retrieve elements from arrayCopy codeThe Code i

the API interface. In fact, many of the Java API is relative, in this way to learn, and soon you will find that you know a lot.public class stringtest{public static void Main (string[] args) { StringBuilder sb = new StringBuilder (); for (int i = 0; I 　　The above is just a small knowledge of my skills to tell you that in the study should learn more extrapolate, Master learning method is you learn programming a shortcut. You are welcome to have a better learning method, learning

tagDocument.stylesheets[0].rules[0]When you prevent clicking on an empty link, the page is often reset to the top end of the page.Previous page SourceAsp:Request.ServerVariables ("Http_referer")Javascript:Document.referrerFreeing memoryCollectGarbage ();Disable Right-clickDocument.oncontextmenu = function () {return false;}Prohibit saveDisable selection of Prohibit pasteAddress bar iconFavicon.ico name Best not change 16*16 16 colors, put the virtual directory under the root directoryFavorites

Programming tips: four tips for making C language efficient-general Linux technology-Linux programming and kernel information. For details, see the following. Writing efficient and concise C language code is the goal pursued by many software engineers. This article describes some experiences and experiences in programming. First move: Change Time with Space The biggest contradiction in computer programs i

Css background image tips and pitfalls, css background image tips Background Image settings of the body First: In this case, the background image can be scaled but not completely proportional. Background: url (imgs/1.jpg) no-repeat; Background-position: center 0; Positioning origin of the background image, due to the high body uncertainty Background-attachment: fixed; the background image remains fixed and

Some tips-refactoring, tips-refactoring Use box-shadow to create relief effects Simple background modification using box-shadow Insufficient background image for long pages ...... 01 UseBox-shadowManufacturing embossed Effect Demo example: The sample html structure: Css: .box { position: relative; border-radius: rem(40px); overflow: hidden; box-shadow: rem(4px) rem(14px) rem(23px

CSS style setting tips and css style tips In-Row Element center setting: If the set element is a text, image, or other in-Row ElementParent ElementSettext-align:center. The sample code is as follows: HTML code Centered setting of fixed width block elements: the elements that meet the conditions of fixed width and block can be centered by setting the "Left and right margin" value to "auto. The sample code i

+, winphone8+================== ========================================== */.flex{display:-webkit-box;display:-webkit-flex;display:-ms-flexbox ;d Isplay:flex;}. Flex-v{-webkit-box-orient:vertical;-webkit-flex-direction:column;-ms-flex-direction:column;flex-direction: Column;}. Flex-1{-webkit-box-flex:1;-webkit-flex:1;-ms-flex:1;flex:1;}. Flex-align-center{-webkit-box-align:center;-webkit-align-items:center;-ms-flex-align:center;align-items:center ;}. Flex-pack-center{-webkit-box-pack:center;-we

(Self.blankpageview) {[Self.blankpageview Removefromsuperview]; Self.blankpageview = nil; }} @endCall:Network error, display error page [Self.view Showneterrorpageview]; [Self.view configreloadaction:^{ NSLog (@ "Refresh"); }]; Hide Network error page [Self.view Hideneterrorpageview]; --------------------------------------------------------- //No Data display blank page [Self.view Showblankpageview]; No data hidden blank page [Self.view Hidebl

Git should save more developers ' jobs than other technologies. As long as you often use Git to save your work, you'll always have the opportunity to return the code to the previous state, so you can undo the mistakes you made in the middle of the night. In spite of that, Git's command-line interface is a tricky one to grasp. Next, give you 7 tips to maximize the role of Git. Typically, most of the time we use only add, commit, Branch, and Push/pull

attention.His works are short, gorgeous costumes, beautiful music, dialogue humorous, sophisticated ideas. Today, scientific and technological innovation and rapid development of civilization, however, now the audience, still have no patience, just as the audience in Shakespeare's time. A few tips for building focus Attention is a very abstract noun, and capture attention is like "Tiger Eat Day" like, no way, like other media, users browsing web

Tags: SQL development data rem BST concat statements Col Mon create First, the ranks of the conversion Basic ideas: 1. Conversion of data into tender data, 　　　　　　 2. Use Cartesian product for row and column conversion Selectsum ( Case whenChildr='Dining' Then Money End) as 'Dining', SUM ( Case whenChildr='Communication' Then Money End) as 'Communication', SUM ( Case whenChildr='Entertainment' Then Money End) as 'Entertainment' from (SelectChildr,Convert(sum( Money),decimal(Ten,2)

Interview tips for C and C ++ programmers and interview tips for programmers Many advanced languages use C/C ++ for reference. Therefore, the C/C ++ language is very important for software developers. The interview tips for C and C ++ programmers is a book that resolves the questions in C/C ++ and helps job seekers better prepare for the interview. The "intervi

There are some tips and tricks in Ubuntu. I will share with you the tips and tricks I know. TIPS: 1. Quickly search for the top left corner. Click "quick access" (the Windows key on the keyboard is also OK). You can also search and find the program. 2. What is xuanjicang in the left sidebar? Right-click the icon and try it. It is similar to right-click Win7. 3. P

Php date Operation TIPS and php Operation TIPS. Php date Operation TIPS, php Operation TIPS summary This article summarizes the php date operation skills. For your reference, I will share with you the following details: 1. php will summarize the date php date Operation TIPS

8 tips commonly used in PHP website development, and php website development tips. PHP website development tips: php is a server scripting language used to create dynamic web pages. Like ASP and ColdFusion, users can mix eight tips commonly used in PHP website development and php website development

Android code optimization tips and android code tips This article mainly introduces some optimization tips for small details. When these tips are used in a comprehensive manner, they still play a role in improving the performance of the entire App, but they cannot greatly improve the performance. Choosing an appropriat