小猪爱拱地

n this article, we will see the memory layout of different C++ Object. And how different storage & access specifiers affect this memory footprint. I am not going to discuss compiler augmented code, name mangling & working of any C++ mechanism relat

如果是多继承，并且 upcast到不同的接口的时候，需要用dynamic_cast比如，下面的代码，第37行一定要用 dynamic_cast,因为它是从一个 基类接口转到另外一个基类借口。 1 class A 2 { 3 public: 4 virtual bool IsA(void) = 0; 5 protected: 6 int t_a; 7 }; 8 9 class B 10 { 11

今天遇到了一个 leetcode报的错：Line 48: Char 21: runtime error: store to misaligned address 0x61400000009e for type 'char *', which requires 8 byte alignment [solution.c]0x61400000009e: note: pointer points here61 00 62 00 be be be be be be be be be be be be b...

1. 插入排序void insert_sort(int *nums, int s, int e){ int i, j; for(i = s+1; i <= e; ++i) { j = i-1; int k = nums[i]; while( j >= s && nums[j] > nums[i])

Cable masterTime Limit: 1000MS Memory Limit: 10000K Total Submissions: 83304 Accepted: 16926 DescriptionInhabitants of the Wonderland have decided to hold a regional programmin...

"%f" is the (or at least one) correct format for a double in printf. There is no format for a float, because if you attempt to pass a float to printf, it'll be promoted to double before printf rece...

代码如下:#include #include #include  #define SIZE_BYTE 10int main( void){ int i; char *buff; buff = (char *)malloc( SIZE_BYTE); (char *)memset(buff,'a',SIZE_BYTE); for(i=0;i<SIZE_BYTE;i

Smart pointer uses RAII(Resource Acquisition is Initialization) idiom to manage resource.  The C++ 11 standards accept it as first class library member, and it resides in namespace std, instead of n

http://eli.thegreenplace.net/2012/12/17/dumping-a-c-objects-memory-layout-with-clangWhen one wants to understand the memory layout of structures and classes, the C/C++ operatorssizeof and offset

The C++ provides a feature called function overloading. This enables you to write many functions with same name, provided each function takes parameters of different types. The lower level languages (

假设有个文件如下：$ cat test.c int foo(int a){ return 1;}编译如下：$ g++ test.c -c $ nm test.o 00000000 T _Z3fooi可见， c++ 编译器对名字做了修饰。再编译如下：$ gcc -c test.c $ nm test.o 00000000 T foo可见，

1. sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EFecho "deb http://download.mono-project.com/repo/debian wheezy main" | sudo tee /e

代码如下： class T { public : T(); virtual int f(void); private : int d; };T::T(void){ d = 0x12345678;}int T::f(void){ return 12;}void x(T& t) {

１．help()&gt;&gt;&gt; help()Welcome to Python 3.5's help utility!If this is your first time using Python, you should definitely check outthe tutorial on the Internet at http://docs.python.org/3.5/...

默认的情况下，右移的结果是向下取整的。比如，-3&gt;&gt;1，　移位的时候结果是 -2,而不是 -1;合理的结果应该是-1(取靠近０的整数值）。下面的代码展示了获得合理的结果的一个技巧：#include &lt;stdio.h&gt;int main(void){    int x = -12340;    double y = (double)(x) / 16;    in...

extern "C"是为了让代码按照C的方式编译，链接。$ cat 1.h#ifdef __cplusplusextern "C" {#endifvoid foo(void);#ifdef __cplusplus};#endif$ cat 1.cpp #include "1.h"void foo(void){}$ g++ 1.cpp -c$ objd...

在做一道题目的时候，写了下面一行代码：ret = ret << 8 + data[i];本意是把 ret的值左移8位，然后加上 data[i].但是，实际上，因为 +的优先级高于 <<, 实际的结果是 把 ret 左移 ret+data[i]位。。查了半天才发现。。代码应该写成：ret = (ret << 8) + data[i];...

In my opinion, it is much more beneficial learning a high level language than a specific architecture assembler. But I fancied learning some ARM assembler just for fun since I know some 386 assembler.

We saw in chapter 1 and chapter 2 that we can move values to registers (using mov instruction) and add two registers (usingadd instruction). If our processor were only able to work on registers

就不解释了，直接上代码：/** * \file callback3.cc * \author Michael Egli * \date 08-Mar-2015 * \copyright 2015 wisol technologie GmbH * * Overview * ======== * * Shows how to store callbacks with differ

C++ and The Perils of Double-Checked Locking: Part I In this two-part article, Scott and Andrei examine Double-Checked Locking.Google the newsgroups or Web for the names of design patterns, and you’re

Between the time you type in some C/C++ source code and the time it executes on a CPU, the memory interactions of that code may be reordered according to certain rules. Changes to memory ordering are

The double-checked locking pattern (DCLP) is a bit of a notorious case study inlock-free programming. Up until 2004, there was no safe way to implement it in Java. Before C++11, there was no safe

In this installment, Scott and Andrei examine the relationship between thread safety and thevolatile keyword.In the first installment of this two-part article, we examined why the Singleton patt

今天遇到一个 std::string 字符串crash的问题。问题代码如下面：#include int main(void){ std::string str; char *str2 = 0x00; str = str + "hello" + str2; return 0;}crash的时候，调用栈如下：(gdb) bt full#0 strlen ()

To implement virtual functions, C++ uses a special form of late binding known as the virtual table. Thevirtual table is a lookup table of functions used to resolve function calls in a dynamic/late b

最新的 c++11标准整合进了 线程支持，下面写一个小程序测试一下。测试代码：#include #include void hello(void){ std::cout << "Hello concurrent world" << std::endl;}int main(void){ std::thread t(hello); t.join();}编译方法：

假定源文件如下：#include #include class IA{public:virtual ~IA() {}virtual void PrintA() = 0;virtual void PrintB() = 0;virtual void PrintC() = 0;};class A : public IA{public:A();~A();void Pr

1. 下载ruby源代码，编译，安装2. 使用发行版自带的安装包，安装3. 使用 rvm安装。这种方法如下：3.1curl -L https://get.rvm.io | bash -s stable这一步主要是准备 rvm 环境，并且下载 ruby最新版本。安装目录是 $HOME/.rvm3.2 source ~/.rvm/scripts/rvmrvm

错误是这样的：$ curl -L get.rvm.io | bash -s stable --ruby % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent

为什么有这个？由于国内网络原因（你懂的），导致 rubygems.org 存放在 Amazon S3 上面的资源文件间歇性连接失败。所以你会与遇到 gem install rack 或 bundle install的时候半天没有响应，具体可以用 gem install rails -V 来查看执行过程。这是一个完整 rubygems.org 镜像，你可以

执行bundle install --without development test时，走到Installing mysql2 0.3.19 with native extensions这一步后就一直停在这里。后来发现是没有安装 mysql的dev文件。执行 sudo aptitude install libmysqlclient-dev后，就能继续往下

下面摘自 http://en.cppreference.com/w/cpp/language/destructorTrivial destructorThe destructor for class T is trivial if all of the following is true:The destructor is not user-provided (meanin

ARM claims that Thumb-2 instructions (for ARM Cortex cores and all ARMv7 processors) provides performance improvements and code size optimization:Thumb-2 technology is the instruction set underlyi

C++11 Tutorial: Introducing the Move Constructor and the Move Assignment OperatorAugust 6, 2012 byDanny Kalev 9 CommentsCopy constructors sounds like a topic for an article f