C++ Pointers (AGAIN AGAIN) and passing by value or reference.

 

PASSING BY VALUE

// class declaration
class Foo {}; 

void PassByValue(Foo f, int n)

{
  // Do something with f and n.
}  

int main() 

{
  Foo foo;
  int i = 1;
  PassByValue(foo, i);
}

 

PASSING BY POINTER

class Foo 

{
 public:
  int data[100];
}; 

void PassByPointer(Foo* f, int n)

{
  // Do something with *f and n.
} 

int main()

{
  Foo foo;
  int i = 0;
  PassByPointer(&foo, i);
  return 0;
}

 

PASSING BY REFERENCE

class Foo 

{
 public:
  int data[100];
}; 

void PassByReference(Foo& f, int n)

{
  // Do something with f and n.
} 

int main()

{
  Foo foo;
  int i = 0;
  PassByReference(foo, i);
  return 0;
}

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