class A
{
public:
    mutable int x;
   A()
   {
      static int i = 0;
      x = i;
      i++;
      std::cout << " A()" << std::endl;
   }
   ~A()
   {
       std::cout << "~A()" << std::endl;
   }
   void foo() const
   {
       x = 1;
   };
};

class B
{
public:
   const A & a;
   B(const A & a) : a(a)
   {
       std::cout << " B()" << std::endl;
   }
   ~B()
   {
       std::cout << "~B()" << std::endl;
   }
   void doSomething()
   {
       a.foo();
   };
};

int main()
{
   B b((A()));
   b.doSomething();
}

class B
    {
    public:
            const std::string & a;
            B(const std::string & a) : a(a)
            {
                    std::cout << " B()" << std::endl;
            }
            ~B()
            {
                    std::cout << "~B()" << std::endl;
            }
            void doSomething()
            {
                    std::cout << "a = " << a << std::endl;
            };
    };

    int main()
    {
            B b(std::string("I love C++ so much!"));
            b.doSomething();
    }

#include <iostream>

 struct A {
   A(): p(0) {}
   ~A() { if (p) { std::cout << *p << "n"; } }
   int* p;
 };

 int bar0();
 void bar1(int i);

 int main() {
   A a;
   {
     int x = 4; a.p = &x;
   }
   {
     int y = bar0(); bar1(y);
   }
 }

 int bar0() { return 7; }
 void bar1(int i) { std::cout << i << "n"; }

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