ostream& operator<<(ostream &os,const A &a);
class A
{
friend ostream& operator<<(ostream &os,const A &a);
public:
A(int x):a(x)
{
}
~A()
{
}
private:
int a;
};
ostream& operator<<(ostream &os,const A &a)
{
os<<a.a<<endl;
return os;
}
int main()
{
A a(78);
cout<<a<<endl;
return 0;
}
