Which of the following ways are legal to access a class data member using this pointer?

1. It can access only other static members of its class.
2. It can be called using the class name, instead of objects.

#include<iostream.h> 
class CuriousTab
{
    static int x; 
    public:
    static void SetData(int xx)
    {
        x = xx; 
    }
    static void Display() 
    {
        cout<< x ;
    }
};
int CuriousTab::x = 0; 
int main()
{
    CuriousTab::SetData(44);
    CuriousTab::Display();
    return 0; 
}

#include<iostream.h> 
int main()
{
    int x = 0;
    int &y = x; y = 5; 
    while(x <= 5)
    {
        cout<< y++ << " ";
        x++;
    }
    cout<< x; 
    return 0; 
}

#include<iostream.h> 
class CuriousTab
{
    int a, b, c; 
    public:
    void SetValue(int x, int y ,int z)
    {
        a = x;
        b = y;
        c = z;
    } 
    void Display()
    {
        cout<< a << " " << b << " " << c;
    } 
}; 
int main()
{
    CuriousTab objCuriousTab;
    int x  = 2;
    int &y = x;
    y = 5;
    objCuriousTab.SetValue(x, ++y, x + y);
    objCuriousTab.Display();
    return 0; 
}

#include<iostream.h> 
class CuriousTabBase
{
    public:
    int x, y; 
    public:
    CuriousTabBase(int xx = 0, int yy = 0)
    {
        x = xx;
        y = yy; 
    } 
 };
class CuriousTabDerived : public CuriousTabBase
{
    private:
        CuriousTabBase objBase; 
    public:
    CuriousTabDerived(int xx, int yy) : CuriousTabBase(xx), objBase(yy)
    {
        cout << this->x   << " " 
             << this->y   << " "  
             << objBase.x << " "
             << objBase.y << " ";
    } 
    ~CuriousTabDerived()
    { }
};
int main()
{
    CuriousTabDerived objDev(11, 22); 
    return 0;
}