#include <iostream>
using namespace std;
class A
{ protected: static int x;
private: int y;
public: A(int i) { x=i; y=-i+4; }
int put_x(A a) { return a.x+a.y; } };
int A::x=7;
int main()
{ A a(10);
cout<<a.put_x(20);
return 0;
}