Structures and Pointers

#include "iostream"
using namespace std;

struct Point
{
    double x,y;
};

void DoublePoint(Point* p);
void Print(Point p);

int main()
{
    Point p1,p2;
    p1.x=9.78;
    p1.y=10.98;
    p2.x=99.01;
    p2.y=22.23;
    Print(p1);
    Print(p2);
    DoublePoint(&p1); //You pass the position of the variable so you have to type &var
    DoublePoint(&p2);
    Print(p1);
    Print(p2);
    system("PAUSE");
}

void DoublePoint(Point* p)
{
    p->x=2*p->x;  //With Pointers you have to use "->" instead of "." and you must not type "*" before the variable because
    p->y=2*p->y;  //the program is using structures
    return;
}

void Print(Point p)
{
    cout<<p.x<<' '<<p.y<<endl;
    return;
}