trove collections

Objective In software development, collections are inevitably used, and collections in C # represent arrays and several collection classes. Whether they are arrays or collection classes, they have their own pros and cons. How to use a good collection is a skill we must master in the development process. Do not underestimate these techniques, and once you have used the wrong set or approach to the collectio

In software development, collections are inevitably used, and collections in C # represent arrays and several collection classes. Whether they are arrays or collection classes, they have their own pros and cons. How to use a good collection is a skill we must master in the development process. Do not underestimate these techniques, and once you have used the wrong set or approach to the collection in develo

Java Collections. sort () implements the default List sorting methods and custom methods [convert], collections. sort sorting 1. default list sorting method provided by java Main Code: List List. add ("Wang Shuo ");List. add ("Li Ming ");List. add ("Liu Di ");List. add ("Liu Bu "); // AscendingCollections. sort (list, Collator. getInstance (java. util. locale. CHINA); // note: the sorting is based on the p

The difference between Collection and Collections: collections1. java. util. Collection isParent interface of the Collection framework. It provides common interface methods for basic operations on collection objects. The Collection interface has many specific implementations in the Java class library. The Collection interface provides a unified operation mode to maximize various specific sets. CollectionShortlist│ Invalid parameter list│ ├ ArrayList│

When doing the project encountered a kind of situation, is to compare two sets of the same elements, after looking for data, found the collections class of the disjoint methodHere's a small example:1 Importjava.util.Collections;2 ImportJava.util.HashSet;3 ImportJava.util.Set;4 5 Public classDemo {6 7 Public Static voidMain (string[] args) {8SetNewHashset();9SetNewHashset();Ten OneSet1.add ("1"); ASet1.add ("1111"); -Set1.add ("2222"); -

A1, when the application A3 the first point to A2 the entire array, and the last of the A2 point to the new array, and then the A2 point to the Wei line disconnects, pointing to the new array, so that the formation of a double-chained collection of memoryAs a method: To add a method forward, and back to add, back to add directly into the E is OK, because the previous method of writing is to add backwardsSuch as: is the method of deleting the previous dataSuch as: is the method to delete the fol

;>> A[5, 1, 2, 3, 1, 1, 2, 3, 4, 5, 6, 7]7. Modifying list values>>> a[0] = ' 5 '　　　　　>>> A[' 5 ', 1, 2, 3, 1, 1, 2, 3, 4, 5, 6, 7]8. Delete list valuesPop () Delete the element and return the deleted value by default delete the last element, you can specify a location to delete　　　　　　>>> A.pop ()7>>> A.pop (0)' 5 'Remove () deletes the specified element when there are multiple identical elements when the first one in the list is deleted　　　　　　>>> A　　　　　　[1, 2, 3, 1, 1, 2, 3, 4, 5, 6]>>> A.remove

)classuser{PUBILCintuser_id; PUBILCstringuser_name;}New LinstNewLinst();Insert User SJ=Newuser (); sj.user_id=1; Sj.user_name="Zhang San"; I.add (SJ); user LS=Newuser (); ls.user_id=2; Ls.user_name="John Doe"; I.add (LS);foreach(User Xinchi) {Console.WriteLine (x.user_id);}listAdd toI.add (e.g. 123);Regular expressions stringstr ="\""; stringtemp =Console.ReadLine (); Regex Rx=NewRegex ("\\d"); if(Rx. IsMatch (temp)) {Console.WriteLine ("non-negative integers"); }Else{Console.WriteLine ("is not"

Collections writing guide in Ruby and Ruby collections writing guide Preference array and the literal representation of Hash (unless you need to pass parameters to their constructor ). # bad arr = Array.new hash = Hash.new # good arr = [] hash = {} When you need an array with elements of words (no spaces or special characters), you always use % w to define a string array. Apply this rule to only two