C++ future 使用demo

#include 
#include 
#include 
#include 
#include 

class MyClass {
 public:
  int func2(int x, int y) {
    return x + y;
  }
};
using namespace std;
int main() {
  //计算（a+b）/(x+y)
  //用三个线程，一个线程计算a+b，另一个线程计算x+y
  int a, b, x, y;
  a = 10, b = 8, x = 2, y = 4;

  MyClass my_class;

  int sum1, sum2;
  //模板传参的时候使用ref，否则传参失败
  vector> futrues;

  auto future1 = std::async(std::launch::async, &MyClass::func2, my_class, x, y);
  futrues.emplace_back(std::move(future1));

  auto future2 = std::async(std::launch::async, &MyClass::func2, my_class, a, b);
  futrues.emplace_back(std::move(future2));

  //获取值
  for (int i = 0; i < futrues.size(); i++) {
    std::cout << "sum1=" << futrues[i].get() << std::endl;

  }
  return 0;
}