Detect common base class

Suppose one has a class hierarchy, without multiple inheritance: struct TOP{}; struct L : TOP{}; struct R : TOP{}; struct LL : L{}; struct LR : L{}; struct RL : R{}; struct RR : R{}; Is it possible to write a metafunction that will return the type of the common base of two types? (it could return void if not common base class exists.) For example common_base<RR, R>::type == R common_ba

检测通用基类

假设有一个类层次结构,没有多重继承: struct TOP{}; struct L : TOP{}; struct R : TOP{}; struct LL : L{}; struct LR : L{}; struct RL : R{}; struct RR : R{}; 是否可以编写一个元函数来返回两种类型的公共基类型? (如果不存在通用基类,它可能会返回void 。)例如 common_base<RR, R>::type == R common_base<RL, RR>::type == R common_base<LL, RR>::type == TOP common_base<LL, std::stri

What's time complexity of this algorithm for solving Sudoku?

Sudoku Solver Write a program to solve a Sudoku puzzle by filling the empty cells. Empty cells are indicated by the character '.'. You may assume that there will be only one unique solution . Personally I think, time complexity = O((n^2)!), n is the number of rows(cols) of the board. C++ class Solution { public: void solveSudoku(vector<vector<char> > &boar

这个算法用于解决Sudoku的时间复杂度是多少?

数独求解器 编写一个程序,通过填充空单元格来解决数独谜题。 空单元格由字符'。'表示。 你可能会认为只会有一个独特的解决方案 。 我个人认为, 时间复杂度= O((n ^ 2)!),n是电路板的行数(cols)。 C ++ class Solution { public: void solveSudoku(vector<vector<char> > &board) { // Input validation. if (board.size() == 0 || board.size()

How to install clang header files?

I have clang installed on my MacOS (in /usr/bin/clang ) which I think comes installed by default on Mac, however, when I try to include clang header files in a script, it says they are not found Example.cpp:1:10: fatal error: 'clang/Driver/Options.h' file not found Question: is it necessary (and possible, if so, how) to install the header files when clang is already installed and built on the M

如何安装clang头文件?

我在我的MacOS上安装了clang(在/ usr / bin / clang中),我认为它默认在Mac上安装,但是,当我尝试在脚本中包含clang头文件时,它表示找不到它们 Example.cpp:1:10: fatal error: 'clang/Driver/Options.h' file not found 问题:如果已经在MacOS系统上安装并构建了clang,那么是否需要(也可能,如果是这样)安装头文件(或者是否需要在所有期望的开发工具包同时重新安装clang本身和他们的头文件被安装)? #include "clang

How to handle a transitive dependency conflict using Git submodules and CMake?

We have a number of Git repositories, some containing our own code and some containing slightly modified third-party library code. A simplified dependency graph looks like this: executable_A | | | v | library_B | | v v library_C So the executable has two dependencies on library_C , one direct and one transitive. I am hoping to tie this all together us

如何使用Git子模块和CMake处理传递依赖冲突?

我们有许多Git仓库,其中一些包含我们自己的代码,一些仓库包含稍微修改的第三方库代码。 简化的依赖关系图如下所示: executable_A | | | v | library_B | | v v library_C 所以可执行文件对library_C有两个依赖关系,一个是直接的,另一个是可传递的。 我希望使用Git子模块和CMake将它们结合在一起,因此简化的目录结构如下所示: executable_A/ CMakeListst.txt library_B

Thread created by static object deleted before DTor?

I have the following classes in my code. In other words, There is a static object (singletone) which creates thread in CTor, and when its DTor is called, it has some work to be done in the context of this thread (DTor puts some jobs for the thread). The problem that i face is that when the DTor of B is called there are no other threads running in the process - seems like this thread is killed

在DTor之前删除静态对象创建的线程?

我的代码中有以下类。 换句话说,有一个静态对象(singletone),它在CTor中创建线程,当它的DTor被调用时,它在这个线程的上下文中有一些工作要做(DTor为线程放置一些工作)。 我面对的问题是,当调用B的DTor时,在进程中没有其他线程正在运行 - 看起来像调用B类的析构函数之前,线程被进程清除所杀死。 任何人都知道这是为什么发生? 以及如何避免它? UPD:只有从DLL创建单例时,问题才会发生。 从同一个可执行文件

Why does every STL container have a swap function defined as a member function?

Consider the queue container in STL. It is my understanding that swap() available in the <algorithm> header would work just fine. I understand that swap() will only copy the queue instances superficially, that is, only the front and rear pointers will be copied, along with the size , and other data members. The entries in the two queues would not physically swap places, but I do not s

为什么每个STL容器都有一个定义为成员函数的交换函数?

考虑STL中的queue容器。 据我的理解, <algorithm>头文件中提供的swap()可以正常工作。 我知道swap()只会表面复制queue实例,也就是说,只有front和rear指针会随着size和其他数据成员一起被复制。 两个队列中的条目不会在物理上交换位置,但我不明白为什么在任何情况下都需要这样做,因为一旦交换了指针和大小,两个队列就会有效地交换。 在C ++ 11引入移动语义之前, std::swap的通用实现别无选择,只能做两个副

Why can std::apply call a lambda but not the equivalent template function?

The following code snippet (compiled using gcc 6.3.0 on OS X with -std=c++17) demonstrates my conundrum: #include <experimental/tuple> template <class... Ts> auto p(Ts... args) { return (... * args); } int main() { auto q = [](auto... args) { return (... * args); }; p(1,2,3,4); // == 24 q(1,2,3,4); // == 24 auto tup = std::make_tuple(1,2,3,4); std::experimental:

为什么std :: apply可以调用一个lambda,但不能使用等价的模板函数?

下面的代码片段(在OS X上用-std = c ++ 17编译使用gcc 6.3.0)演示了我的难题: #include <experimental/tuple> template <class... Ts> auto p(Ts... args) { return (... * args); } int main() { auto q = [](auto... args) { return (... * args); }; p(1,2,3,4); // == 24 q(1,2,3,4); // == 24 auto tup = std::make_tuple(1,2,3,4); std::experimental::apply(q, tup); // == 24 st

Visual Studio 2010 project not compiling

I have a visual studio project in 2010 installed on two different laptops, one with windows 7 and other one with windows 10. But the thing is that when i compile on windows 10 i get the errors: Error 3 error C2338: CVarTypeInfo< char > cannot be compiled with /J or _CHAR_UNSIGNED flag enabled C:Program Files (x86)Microsoft Visual Studio 10.0VCatlmfcincludeatlcomcli.h 1751 1 PRJ_

Visual Studio 2010项目不编译

我在2010年安装了一个Visual Studio项目,安装在两台不同的笔记本电脑上,一台使用Windows 7,另一台使用Windows 10.但事情是,当我在Windows 10上编译时,出现以下错误: Error 3 error C2338: CVarTypeInfo< char > cannot be compiled with /J or _CHAR_UNSIGNED flag enabled C:Program Files (x86)Microsoft Visual Studio 10.0VCatlmfcincludeatlcomcli.h 1751 1 PRJ_var Error 4 error C2338: CVarT

advanced Collision detection?

Hi i'm currently making an RPG similar to Legend of Zelda. I have a feature in my game where when Player attacks enemy with his sword, the enemy is knocked back n units. i have a collision detection that sometimes works as intended, and other times the enemy goes through the wall and gets stuck on the other side, and then other times the enemy can simply walk right through the wall. If pos

先进的碰撞检测?

嗨,我目前正在制作类似于塞尔达传说的RPG。 我的游戏中有一个特点,当玩家用剑攻击敌人时,敌人被击退n个单位。 我有一个碰撞检测,有时按预期工作,有时候敌人穿过墙壁并卡在另一边,然后有时候敌人可以直接穿过墙壁。 如果可能的话,让敌人在与墙相撞时向玩家移动将是我相信这个问题的一种可能的解决方案,但我不知道如何实现这一点。 这是我目前的碰撞代码: // Enemy Collides with Wall counter1 = 0;

AABB Collision response(Push back colliding objects)

I'm having problem with collision detection with my C++ game. I first tried AABB and successfully got it to detect collision but the problem was that I want to be able to push each other so I went with a basic solution to push both objects back half of the distance penetrated. But that only pushed the objects to a 45 degree angle to each other.Link to GIF explaining what i mean IF YOU DON

AABB碰撞响应(推回碰撞物体)

我在用C ++游戏碰撞检测时遇到了问题。 我首先尝试了AABB并成功地检测到了碰撞,但问题是我想能够互相推送,所以我采用了一种基本解决方案,将两个物体推回到距离的一半。 但是,只是将对象彼此推到45度角。链接到GIF解释我的意思 如果您不想阅读本段落 所以我认为我需要一个方向来推入对象,所以我试图从教程中修改一些代码。 方向是两个对象中心之间的归一化矢量。 然后,一半的碰撞深度乘以归一化的矢量,以便它们被