Cpp深入：就要在main函数之前执行

#include <iostream>
using namespace std;
class CompileRequirements
{
public:
	CompileRequirements()
	{
		// 需要在main函数之前调用的初始化工作
		cout << "before main function." << endl;
	}
};
CompileRequirements c;
int main()
{
	cout << "in main function ." << endl;
	return 0;
}