#include <iostream>

class Bar
{
    size_t len_;
public:
    Bar(size_t len) : len_(len) {std::cout << len << '\n';}
};

class Foo : virtual public Bar //virtual inheritance
{    
    size_t foo_bigger_than_bar;
public:
    Foo() : Bar(sizeof(Foo)) { }
};

class Derived2: public Foo
{    
    size_t derived2_bigger_than_foo;
public:
    Derived2() : Bar(sizeof(Derived2)), Foo() { }
};

int main() {
    Foo f;
    std::cout << '\n';
    Derived2 d;
}

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