#include <iostream>
class A
{
public:
A()
{
c = counter++;
};
int c;
private:
static int counter;
};
int A::counter =0;
int main (int argc, char ** argv)
{
A a1;
A a2;
A a3;
std::cout << a1.c << a2.c << a3.c << std::endl;
std::cout << (a2 = a1).c <<std::endl;
std::cout << a1.c << a2.c << a3.c << std::endl;
a2.c = 1;
std::cout << a1.c << a2.c << a3.c << std::endl;
return 0;
}