C++结构到类的演变

#include<iostream>
 
using namespace std;
struct point{
//private:
    double x, y;
//public:
    void setxy(double a,double b)
    {
        x = a; y = b;
    }
        void display(){
            cout << x << "\t" << y << endl;
    }    
};
void main(){
    point a;
    a.setxy(1, 2);
    a.display();
    //cout << a.x << "\t" << a.y << endl;
}