Use of the '&' symbol in C++

This question already has an answer here: The Definitive C++ Book Guide and List 1 answer What are the differences between a pointer variable and a reference variable in C++? 32 answers "&" can mean several different things, depending on the context. The example you gave above is the C++ "reference operator": Need help understanding reference operator(C++) in sp

在C ++中使用'&'符号

这个问题在这里已经有了答案: 最终的C ++图书指南和列表1的答案 C ++中的指针变量和引用变量之间有什么区别? 32个答案 “&”可能意味着几种不同的事情,具体取决于上下文。 你上面给出的例子是C ++“reference operator”: 需要帮助理解特定函数中的引用操作符(C ++) 引用运算符是特定于C ++的。 “&”也可以用作C和C ++中使用的“地址”操作符: C ++中的指针变量和引用变量之间有什么区别? 最后,“&”也可以

Ukkonen's suffix tree algorithm, what is necessary?

Yes I have read this: Ukkonen's suffix tree algorithm in plain English? It is a great explanation of the algorithm but it is not so much the algorithm itself that is killing me but rather the data structure used to implement it. I need the data structure to be as minimal and as fast as possible and I have seen many implementations using only Nodes, some with only edges, some with edges an

Ukkonen的后缀树算法,有什么必要?

是的,我读过这样的内容:简单英语中的Ukkonen后缀树算法? 这是对算法的一个很好的解释,但它并不是算法本身,而是杀死我,而是用来实现它的数据结构。 我需要的数据结构尽可能最小和尽可能快,我看到许多实现仅使用节点,一些只有边,一些有边和节点等。然后有变化,我读的一个网站声称,一个节点不需要指向其父节点的指针,而其他地方则不需要考虑如何管理节点的子节点。 我的想法是使用int start和int * end(指向当前

explanation of O(log n)?

This question already has an answer here: What does O(log n) mean exactly? 32 answers You say that your last example is O(n2), but what's n ??? That's what you should ask yourself. It's usually the size of the vector that the loop runs. The easy case would be to have: std::vector<int> MyVec_A = {1, 2, 3, 4, 5}; std::vector<int> MyVec_B = {1, 2, 3, 4, 5}; for(int

O(log n)的解释?

这个问题在这里已经有了答案: O(log n)是什么意思? 32个答案 你说你的最后一个例子是O(n2),但是n是什么? 这就是你应该问自己的问题。 它通常是循环运行的矢量的大小。 简单的情况将是: std::vector<int> MyVec_A = {1, 2, 3, 4, 5}; std::vector<int> MyVec_B = {1, 2, 3, 4, 5}; for(int i = MyVec_A; i--;) { for(int x = MyVec_B; x--;) { // Do Stuff that are of negligible complex

Implementation of a work stealing queue in C/C++?

I'm looking for a proper implementation of a work stealing queue in C/CPP. I've looked around Google but haven't found anything useful. Perhaps someone is familiar with a good open-source implementation? (I prefer not to implement the pseudo-code taken from the original academic papers). No free lunch. Please take a look the original work stealing paper. This paper is hard to

在C / C ++中实现工作窃取队列?

我正在寻找在C / CPP中正确实施工作窃取队列。 我浏览过Google,但没有发现任何有用的东西。 也许有人熟悉一个好的开源实现? (我不想实施从原始学术论文中获得的伪代码)。 没有免费的午餐。 请看看原来的偷书工作。 这篇文章很难理解。 我知道纸张包含理论证明而不是伪代码。 然而,没有比TBB更简单的版本。 如果有的话,它不会提供最佳性能。 偷工作本身会产生一些开销,所以优化和窍门非常重要。 尤其是,出

Ideas for good performance optimisations in C++

Ok, I've been sitting in front of profiler results over the last three days, generated by running a pretty wide range of test cases through an automation suite. The idea is to see if there are any good optimisations that can generally improve performance. I'll qualify good in this context as follows; Has the potential for performance improvement that are both very significant and obse

在C ++中优化性能优化的想法

好的,在过去的三天里,我一直坐在profiler结果前面,通过一个自动化套件运行相当广泛的测试用例。 这个想法是看看是否有任何可以提高性能的优化优化。 我将在这方面具备以下条件: 绩效改进的潜力在终端用户水平上都非常显着且可观察到,例如,表现不佳的地区的绩效改善> 100%。 减少核心空间使用的潜力,例如数据大量减少> 50%。 易于实现,对代码的混淆最少,副作用最小。 即实施优化的好处大大超出了成本。

Optimizing for space instead of speed in C++

When you say "optimization", people tend to think "speed". But what about embedded systems where speed isn't all that critical, but memory is a major constraint? What are some guidelines, techniques, and tricks that can be used for shaving off those extra kilobytes in ROM and RAM? How does one "profile" code to see where the memory bloat is? PS One could arg

在C ++中优化空间而不是速度

当你说“优化”时,人们往往会认为“速度”。 但是嵌入式系统的速度并不是那么重要,但内存是一个主要的限制因素呢? 什么是一些指导方针,技巧和技巧可用于削减ROM和RAM中的额外千字节? 一个“配置文件”代码如何查看内存膨胀的位置? PS有人可能会争辩说,在嵌入式系统中过早地优化空间并不是那么糟糕,因为你为数据存储和蠕变提供了更多的空间。 它还允许您降低硬件生产成本,因为您的代码可以在较小的ROM / RAM上运行。 P

Detecting Chess moves from successive image differences using OpenCV tools

Hey, I am coding up a simple chess playing robot's vision system, I am trying to improve on some previous research to allow camera and a standard chess set be used and both be allowed to move during the game. So far I can locate the board in an image acquired via web-cam, and I want to detect moves by taking difference of successive images to determine what has changed then use previous info

使用OpenCV工具检测国际象棋从连续的图像差异中移动

嘿,我正在编写一个简单的国际象棋机器人的视觉系统,我正试图改进一些以前的研究,以允许使用相机和标准国际象棋套装,并允许在游戏中移动。 到目前为止,我可以在通过网络摄像头采集的图像中找到该电路板,并且我希望通过对不同的连续图像进行检测来确定发生了什么变化,然后使用之前关于电路板占用情况的信息来检测移动。 我的问题是我目前似乎无法可靠地检测到变化,我目前的流水线如下所示:减去两个图像 - >直方图均

Setting text input focus within a QWebView

I'm trying to display a Google login dialog in a QWebView, and as I recall, Google likes to set your keyboard focus to the first input field on the page (in this case, the e-mail field). Unfortunately, the QWebView widget doesn't actually respect this behaviour, and therefore loads the page with keyboard focus on nothing at all: So I decided dig about a little, and inserted this code

在QWebView中设置文本输入焦点

我试图在QWebView中显示Google登录对话框,并且我记得Google喜欢将您的键盘焦点设置为页面上的第一个输入字段(在本例中为电子邮件字段)。 不幸的是,QWebView小部件实际上并不尊重这种行为,因此加载页面的时候一点关键都没有: 所以我决定挖掘一下,并将这段代码插入到我的类逻辑中: void GoogleAuthDialog::pageLoaded(bool ok) { if (ok) { ui->webView->setFocus(); ui->webView->pa

QMainWindow does not regain focus after QDialog is closed

As a follow-up for this question: I have a QMainWindow that opens a QDialog. When the QDialog is closed the focus is "lost" - the QMainWindow doesn't get it back and no other widget seems to have it (actually, there are no active widgets besides those two). How can I enforce the regaining of the focus by QMainWindow? Currently I'm doing this in the eventFilter of my QMainWI

QDialog关闭后,QMainWindow不会重新获得焦点

作为这个问题的后续行动: 我有一个打开QDialog的QMainWindow。 当QDialog关闭时,焦点会“丢失” - QMainWindow无法恢复,并且没有其他小部件似乎拥有它(实际上,除了那两个之外,没有活动小部件)。 我如何通过QMainWindow强制重新获得焦点? 目前我在我的QMainWIndow的eventFilter中执行此操作: if(!hasFocus()) { setFocus(); } 但是,我担心这种修复是错误的,并且可能会导致我现在无法想象的错误... 更新+

Use dialog controls without stealing focus

I have a modeless CDialog that contains controls, some CButtons and a CScrollbar. The CDialog is parented off of an edit box that I want to keep focus at all times. The problem is that whenever the user uses the controls, clicking a button or on the scrollbar, the control steals focus from the edit box, causing both the parent window to draw without focus (grayed-out header bar), and causing th

使用对话框控件而不偷窃焦点

我有一个无模式的CDialog,它包含控件,一些CButtons和一个CScrollbar。 CDialog是一个我希望始终关注的编辑框。 问题是,无论何时用户使用控件,单击按钮或滚动条上,控件都会从编辑框中窃取焦点,导致父窗口不带焦点地绘制(灰色标题栏),并导致控件采取所有的键盘输入。 有没有一种方法可以让控件响应鼠标操作而不是窃取焦点? 控件和对话框都是用WS_CHILD创建的。 这些控件是对话框的父对象,并且该对话框是编辑框的