practice of programming

is compared, if the same, it means that there has not been a write operation, the result of the original traversal is returned, if not the same, the process is repeated again, if not the same, It is necessary to lock all the segment and then one through. Public intsize () {//Try a few times to get accurate count. On failure due to//continuous async changes in table, resort to locking. FinalSegment This. Segments; intsize; BooleanOverflow//true if size overflows LongSum//Sum of mo

to define more information that you need.Extended ThreadpoolexecutorThreadpoolexecutor has some life cycle methods: BeforeExecute, AfterExecute, and terminated. These methods can be overridden to implement statistical and monitoring functions.The parallelization of recursive algorithmWhat kind of situation can be parallel?For example, for the loop to do something, and these things are independent of each other. Then these things can actually be done in parallel (for loop is serial execution).Th

). However, this approach can reduce code readability and execution efficiency. If you want to include only the header files, do notThis alternative is good. Of course, the. cc file requires a defined portion of the class that is used anyway, and it will naturally contain several header files.Note: It is not dependent on the definition to be able to rely on the declaration.This rule works far beyond what we thought it would do (at least in my own experience). In a medium-sized project, the heade

follows:if __name__=="__main__": #BSTHead1 = Node (9) Head1.left= Node (8) Head1.right= Node (10) Head1.left.left= Node (7) Head1.left.right= Node (9) Head1.right.left= Node (9) Head1.right.right= Node (11) Print(Is_bst_recur (HEAD1))#True Print(Is_bst_unrecur (HEAD1))#True #Not BSTHead2 = Node (9) Head2.left= Node (8) Head2.right= Node (1) Head2.left.left= Node (7) Head2.left.right= Node (9) Head2.right.left= Node (9) Head2.right.right= Node (11) Print(Is_bst_recur (HEAD2))#Fals

Practice content: Create classes dynamically using type1 __author__='Orcsir'2 3 4 @classmethod5 defClass_method (CLS):6 Print("I am Class_method ...")7 8 9 @staticmethodTen defStatic_method (): One Print("I am Staticmethod ...") A - - def __init__(self, x, y): theself.x =x -SELF.Y =y - - + defFool (self): - Print("I am fool ....") + A at #type (name of the class, - #tuple of the parent class (for inheritance, can is empty), - #dictio

() + - def_recv (self): + whileTrue: A Try: atdata = SELF.SOCK.RECV (1024) - except: - self.sock.close () - return - ifData: -Logging.info ("recv: {}". Format (Data.decode ())) in Else: - self.sock.close () to return + - defSend (self, data:str): the Self.sock.send (Data.encode ()) * $ defStop (self):Panax Notoginseng ifSelf.sock: - self.sock.close () the + A defMain (): theCC =chat

First, the grammaruntil [Condition] # and while on the contrary, when the condition condition is established, the loop is terminated, or the program segment that continues the loop does #执行内容done Second, practice Enter the user input parameters until the user enters "end" to end the loopUntilread-p "Plz input a Paramter": paramtest $param = "End" Doecho "$param" Done[Email protected]:~$./test.shPlz input a paramter:aaplz input a paramter:bb

Practice content: Use two ways to implement dictionary access attribution: Use a class wrapper dictionary so that the dictionary does not use [] to access the element, use the. Dot number to access the element as if it were a property.Mode one: direct manipulation of instance dictionaries in __init__1 __author__='Orcsir'2 3 #Way One4 classattrdict:5 def __init__(self, attrs:dict):6 #direct manipulation of instance dictionaries to avoid the

(!asleep)Countsomesheep ();The program keeps counting sheep when it's not asleep and jumps out of circulation after falling asleep. Because the update to asleep is done in other threads, there is no way for ordinary variables to get the asleep value in time, so it is very appropriate to use the volatile variable.Note that the volatile variable can only guarantee visibility, that is, the variable will always be consistent with the memory variables, but there is no way to ensure atomicity, so if

(!compareandset (prev, next)); return prev; }Public final Boolean compareandset (int expect, int update) { Return Unsafe.compareandswapint (this, valueoffset, expect, update);}Among them, Compareandswap is the abbreviation of CAs. Returns True if Prev and next are not equal. Otherwise, returns false. Finally, it is done through unsafe.The code above indicates that if Compareandset returns True, the while condition is false, exiting the loop and returning the Prev value. If Comparea

First of all, who is V? Who is P? (M I don't think it's a problem)View, should be the implementation of the display logic, in the development of Android, we think that fragment, activity can be considered as view, their main task is to control the display logic, this part of the code is not very often reused. View realizes the business by invoking the business logic of P. The business includes synchronous business (which can be manipulated in the UI thread) and asynchronous tasks (such as networ

Practice of C Programming in Linux (1) -Development Platform Construction . GCC compiler GCC is the most important development tool in Linux. It is the gnu c and C ++ compilers. Its basic usage is as follows: Gcc [options] [filenames] Options is the compilation option. GCC provides more than 100 compilation options, but only a few are frequently used. We will only introduce several common options. Suppose

[Java concurrent programming practice] ----- "J. U. C": CLH queue lock CLH queue is a queue that maintains a group of threads strictly in FIFO mode in AQS. He is able to ensure that there is no hunger and strict first-come Service Fairness. It is a CLH queue node: The node QNode in the clh queue contains a locked field. This field indicates whether the node needs to obtain the lock. If it is set to true

Apriori condition (precondition): Some methods contain a priori condition based on a state. For example, you cannot remove an element from an empty queue, and the queue must be in a non-empty state before the element is deleted. The operation of a state-based priori condition becomes a dependent state operation. In a single thread, if an operation fails to meet a priori condition, it can only fail, but in a concurrent program a priori condition may become true due to an operation performed b

Boolean () Use [] instead of new Array () Use /()/ instead of new RegExp () Use function () {} instead of new function () 6. Note Type Auto-conversionvar x = "Hello"; // typeof X is a stringx = 5; // changes typeof X to a numberJS can turn numbers into strings when doing mathematical operationsvarx = 5 + 7;//x.valueof () is the TypeOf X is a number var x = 5 + "7"; // x.valueof () is the typeof x is a string varx = "5" + 7;//x.valueof () is the typeof x is a s

1, auto Let the compiler determine the type automatically, typeID return type, displacement operationThe source code is as follows://consoleapplication1.cpp: defines the entry point for the console application. //#include "StdAfx.h"#include using std::cout;using Std::endl;using std::cin;int Main (){//auto automatic judgment type, typeid function return typeint x = 5000;int y = 20;Auto z1=x/y;Auto z2=y/x;Char temp;cout typeid(z1). Name () Endl;cout typeid(Z2). Name () Endl;// bit arithmeticint

The assignment of a variable can take a function notation, or it can be assigned with an equal sign.ConsoleApplication1.cpp: Defines the entry point of the console application.//#include "stdafx.h"#include Using Std::cout;Using Std::endl;int main (){coutIntx = 5;Inty (10);Intz = X*y;coutReturn0;}Operation Result:>consoleapplication1.exeHello, world!50This blog all content is original, if reprint please indicate source http://blog.csdn.net/myhaspl/Type can be customized by typedef keyword//consol

than, asymptotic greater than), what is asymptotic, is the difference between the two factors nε. Therefore, between the conditions 1 and 2 there is a certain gap between the same situation 2 and see 3 There is also a certain gap between, for Case 3, but also to see whether the regular conditions are met.Through the above, I believe that I should be clear about these three methods, you may be a little confused, but it doesn't matter, you just lack of examples of guidance, below we look at a few

;}//Output functionvoidoutput (){Person::output ();cout "Seniority:"}};//Main functionvoidMain (){//base classPerson P1 ("A0001","Zhang San","Male"), p2 ("A002","John Doe","female"), P3;P1.output ();//Operator overloadingP3 = p1 + p2;P3.output ();//Student classStudent S1;S1.input ();S1.output ();//Teacher Class//teacher T1;//t1.input ();//t1.output ();} 650) this.width=650; "src=" Http://s3.51cto.com/wyfs02/M01/73/30/wKioL1X3r1fQ-DJIAAEOQVm_ayg462.jpg "title=" 20150915133105.png "alt="

1, install Python, this has nothing to say, directly installed on the line2, do parallel computing, data mining, machine learning and so on generally need to use numpy, this in the Windows version installed a bit of a problem, installation is more troublesome, it is recommended to build the environment on Linux3, install Openmpi, (not very good installed) This online at present there is no better shortcut installation method, generally download the source code, compile and install, today acciden