c++学习笔记之友元

#include <iostream>
#include <string>
#include <vector>
using namespace std;

class Test
{
public:
friend class Other; //声明Other是Test的朋友
friend void bar(const Test &t);
private:
int x_;
int y_;
};

class Other
{
public:
void foo(Test &t)
{
t.x_ = 10;
t.y_ = 20;
}
};

void bar(const Test &t)
{
cout << t.x_ << endl;
}

int main(int argc, const char *argv[])
{
Test t;
return 0;
}