Can someone explain me thoose codes in detail step-by-step.

#ifndef T_HPP_INCLUDED
#define T_HPP_INCLUDED
#include <iostream>
using namespace std;
#include <math.h>
class T{
public:
        static int t;
        T(){++t;}
};

class S:public T{
public:
        static int s;
        S(){++s;}
        ~S(){s++;}
        S test(){
        S ss;
        return ss;
        }
};

int T::t=pow(2,2);
int S::s=sqrt(16);
int main()
{
    T t1;
    S s1,s2,s3;
    s2.test();
    cout<<S::s<<T::t;
    return 0;
}

#ifndef A_HPP_INCLUDED
#define A_HPP_INCLUDED
#include <iostream>
using namespace std;
template<int vred,class tip<
class KlasaA{
private:
    tip i;
    tip j;
public:
    KlasaA(){i=vred; j=vred;}
};
int main()
{
    KlasaA<-2,double>gen1(0,1);
    KlasaA<3,int>gen2;
    return 0;
}

#ifndef B_HPP_INCLUDED
#define B_HPP_INCLUDED
#include <iostream>
using namespace std;

class B:public A{
public:
    void p(){cout<<"A";}
};
void f(A& ra){
    ra.p();
}
int main()
{
   B b;
   b.p();
   f(b);
    return 0;
}

#endif // B_HPP_INCLUDED

#ifndef A_HPP_INCLUDED
#define A_HPP_INCLUDED
#include <iostream>
using namespace std;
class A{
public:
    A(){cout<<"1";}
    virtual void show(){cout<<"2";}
};

class Q:public A
{
public:
    Q(){cout<<"3";}
    void show(){cout<<"4";}
    ~Q(){cout<<"5";}
};

int main()
{
    A a;
    Q q;
    A *pokA;
    a.show();
    pokA=&q;
    pokA->show();
    return 0;
}
#endif // A_HPP_INCLUDED

class A
{
private:
	int a,b;
public:
	A(){a=1; b=2;}
	A(int aa=1,int bb=2){a=aa; b=bb;}
	A(const A& aa){a=aa.a; b=aa.b;}
	void ispis(){
		cout<<++a<<b++;
	}
};

int main()
{
	A a,a2(3,4),a3(a2);
	a.ispisi();
	a2.ispisi();
	a3.ispisi();
}

public static void Main(string[]args)
{
	A a1,a2,a3,a4;
	a1=new A(1);
	a2=new A(2);
	a3=new A(3);
	a4=new A(4);
	a2=a1;
	a3=a2;
	List<a>list=new List</a><a>();
	list.Add(a1);
	list.Add(a2);
	list.Add(a3);
	list.Add(a4);
	a1=a4;
	foreach(A a in list){
		Console.Write(a.a);
        }
}