Constructor question

[spencer.d]

I was writing a brief program testing scope with a class and discovered a line that I do not understand. I fixed the problem but my question remains.

Here is my class.

class aClass
{
public:
  aClass()
  { 
	  std::cout << "i'm alive\n";
  }
  ~aClass()
  { 
	  std::cout << "i'm dead\n";
  }
};

Here is the fixed code. It ouputs "i'm alive" and "i'm dead" then finishes.

int main(int argc, char * argv[])
{
  aClass A;
}

Here is my questionable code.

int main(int argc, char * argv[])
{
  aClass A();
}

I thought that by using A() I would be calling it's constructor. The code compiles but outputs nothing. I tried overloading the () operator, with a similar short message but nothing was outputted. What is the code aClass A() doing? Newbie question, thanks.