定义namespace

namespace man
{
    int count;
}
namespace woman
{
    int count;
}

man::count

woman::count

简写方法

#include <iostream>

std::cout << "Hello World!" << std::endl ;

#include <iostream>

using namespace std;

cout << "Hello World!" << endl ;

#include <iostream>

using namespace std::cout;

cout << "Hello World!" << std::endl ;

The End