Which of the following statement is correct about the program given below?

#include<iostream.h> 
class AptitudeCrack
{
    int x, y; 
    public:
    void SetValue(int &xx, int &yy)
    {
        x =  xx ++;
        y =  yy; 
        Display();
    }
    void Display()
    {
        cout<< x << ' ' << y;
    }
};
int main()
{
    int x = 10;
    int &y = x;
    AptitudeCrack objAptitude;
    objAptitude.SetValue(x , y);
    return 0; 
}