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#include <iostream>
#include <assert.h>

struct CriticalLiveTime {
    ~CriticalLiveTime() {
        std::cout << "critical live time end" << std::endl;
    }
};

struct Abstract {
    friend class Base;
    
    virtual void foo() = 0;
    virtual void stop() = 0;

private:
    virtual ~Abstract(){}

};

struct Base : Abstract {
    virtual void foo() {
        std::cout << "foo base" << std::endl;
    }

void stop() {
        std::cout << "stop" << std::endl;
    }

virtual ~Base() {
        std::cout << "~Base()" << std::endl;
    }

protected:
    Base() {}

};

template <typename T>
struct Holder :  T {
    void foo() {
        T::foo();
    }

void stop() {
        T::stop();
    }

~Holder() {
        T::stop();
    }

};

struct Concrete1 : Base
{
    CriticalLiveTime resource_;
    void foo(){
        std::cout << "concrete1" <<std::endl;
    }

};

//struct Concrete2 : Holder<Concrete1>
//{
//    CriticalLiveTime resource2_;
//    void foo(){
//        std::cout << "concrete2" <<std::endl;
//    }
//};

int main() {
    Holder<Concrete1> c1;
    Holder<Concrete1> c2;
//    Concrete2 c3; // steel need guard for additional resource :(
//    Concrete1 c4; //error, guard needed
    Abstract& a1 = c1;
    Abstract& a2 = c2;
//    Abstract& a3 = c3;
    a1.foo();
    a2.foo();
//    a3.foo();
}

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Compilation time: 0.43 sec, absolute running time: 0.14 sec, cpu time: 0 sec, memory peak: 3 Mb, absolute service time: 0.58 sec