planeswalker collection

1. Traversal of the Map collectionMap--Couples onIdeas:A: Bring all the husbands together.B: Walk through the collection of husbands, get every husband.C: Ask the husband to find his wife.Transformation:A: Get all the keysB: The collection of traversal keys, get each keyC: According to the key to find the value2. code example:1 Packagecn.itcast_01;2 3 ImportJava.util.HashMap;4 ImportJava.util.Map;5 ImportJ

Db.createcollection (name, {capped:true, autoindexid:true, size:1000, max:100})Name: Collection of namesCapped:true whether to enable collection throttlingAutoindex:true (default is True) whether to use _id as the indexsize:1000000 limit the size of the space used by the collection, no Limit by defaultmax:100000 maximum number of bars in the

A set of mathematical meanings, without repeating elements, which must be hashed1. Definitions = Set ()s = {A-i}s = Set (can iterate over objects)2, plusS.add (Element) #增加1个元素, similar to a list of appendS.update (an iterative object) #增加一个可迭代对象, similar to a list of extend3. DeleteS.remove (Element) #元素不存在, quote key errorS.pop () #随机删除并返回1个元素, when the collection is empty, report key errorS.discard (Element) #删除不存在元素的时候, no errorS.clear () #清空集合4.

The following data and code: click here1. Get Data:The number of words from all the articles in 100 blogs, the RSS feeds used here to get the article data, RSS is the XML file format, so you can download a feedparser to parse the XML document. For statistics on how to get each word of each blog, check the generatefeedvector.py file yourself. Do not understand where to welcome the exchange. The file obtained after obtaining is blogdata.txt.2. Grading Classified CollectionThe hierarchical classifi

Java Virtual Machine-garbage collection algorithm, java garbage collection This article mainly introduces the garbage collection algorithm of Java virtual machine.I. Overview Ii. Mark-clear Algorithm Mark-Sweep. Like the name, the algorithm is divided into two steps: Disadvantages:Iii. replication algorithm The replication algorithm is an optimization of tag

On the page of XAML, create a ListBox with x:name as _list1, where each entry in the listbox is ListBoxItemif (_list1. SelectedItem = = NULL)//returns if the selected item of _list1 is empty{Return}Else{var list = _list1. selecteditems;//get all the selected items of _list1listforeach (ListBoxItem item in list){Outlist.add (item);}foreach (ListBoxItem item in outlist)//Avoid removing yourself from the situation, as it involves changes in the dynamic set{if (item. Content.tostring ()! = "Attachme

1. Overview of the HashSet class:(1) No guarantee of Set iteration order(2) In particular, it does not guarantee that the order is constant2. How HashSet guarantees element uniqueness(1) The underlying data structure is a hash table (an array of elements when the list is linked)(2) Hash table relies on the storage of hashes(3) Adding a function bottom-up relies on two methods:• int hashcode ()• boolean equals (Object obj)3. HashSet stores strings and iterates through:(1) The code example is as f

1, the collection interface has two sub-interfaces:List: A linear table that holds the order of elements, allowing for duplicate elements.Set: Does not record the order in which elements are saved, no duplicate elements are allowed. The collection in mathematicsThe methods in the collection interface are as follows:Collection Hierarchical structure:List:ImportJav

PHP Classic algorithm Collection, PHP algorithm collection In this paper, some classical algorithms of PHP are described. Share to everyone for your reference, as follows: 5 people stole a bunch of apples and were ready to split the loot the next day. In the evening, one person walks out, all the vegetables fruit divides into 5 parts, but one more, conveniently throws this to the tree the monkey, oneself f

PHP Classic Questions collection, PHP Classic questions collection This article has analyzed the PHP classics question in detail. Share to everyone for your reference. Specific as follows: Do a bit of PHP on the network topic, unknowingly do now ..... Post the answer for reference. 1. The time format of the day before printing with PHP is 2006-5-10 22:21:21 (2 minutes) $a = Date ("y-m-d h:i:s", Strtotime (

Code from my blog: http://www.taoniwu.com/archives/3234.html all the great god if there is any good advice, thank you for proposing ~~~~~ ? class collection{ protected $url;//Capture Address protected $prefix;//rename file prefix protected $style;//image format to be collected, passing in an array Const PREL = '/(?: http?| HTTPS?): \ /\/(?:[^\.\/\(\)\?] +)\. (?:[^\.\/]+)\. (?: com|cn|net|org) \/(?: [^\.:\] \'\(\)\

In Linux these two days, YUV videos are collected using v4l2 and then encoded as H.264 files. I saved the YUV video to a file and used the pyuv player to play it. The tragedy was that the video screen was played. As follows: The parameters for collecting videos are: Size: 640*480 YUV format: yuyv is yuv422 I always thought it was my code that was wrong, because I used the sample code of v4l2 for the video collection program, and I ran the sample cod

Python log collection server and python log collectionNote: The log collection service of python is thread-safe (locks are used for writing the same file), but it cannot be processed in the case of multiple processes. The Recommended Practice in the official python documentation is to use the tcp server for log collection to ensure secure writing of files. The lo