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c34823a3bd
- 新增现代 C++ 教程的 Preface 章节，包括英文和中文版本 - 添加 C++ Primer 练习代码 - 新增 Learn C++ 教程的 C++ 开发简介章节 - 添加头文件解析文档 - 更新 mkdocs.yml，包含新教程的目录结构 - 修改项目设置，使用 Python 3.10环境
40 lines
823 B
C++
40 lines
823 B
C++
//
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// 7.3.critical.section.b.cpp
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// chapter 7 parallelism and concurrency
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// modern c++ tutorial
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//
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// created by changkun at changkun.de
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// https://github.com/changkun/modern-cpp-tutorial
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//
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#include <iostream>
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#include <mutex>
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#include <thread>
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int v = 1;
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void critical_section(int change_v) {
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static std::mutex mtx;
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std::unique_lock<std::mutex> lock(mtx);
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// do contention operations
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v = change_v;
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std::cout << v << std::endl;
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// release the lock
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lock.unlock();
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// during this period,
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// others are allowed to acquire v
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// start another group of contention operations
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// lock again
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lock.lock();
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v += 1;
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std::cout << v << std::endl;
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}
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int main() {
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std::thread t1(critical_section, 2), t2(critical_section, 3);
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t1.join();
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t2.join();
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return 0;
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} |