Possible to leave recursion prematurely?
There is a way to exit recursion using exceptions, but I wouldn't recommend it. Instead, modify your function to return a bool that indicates whether you've found 0 or not and modify your logic to return from the function without changing path if 0 has been found. Here's the illustration of the idea:
bool Graph::findPath( Room * curRoom )
{
if( curRoom -> myNumber == 0 )
{
cout << "Outside.\n";
//Escape the recursion!
return true;
}
// ...
if (findPath( curRoom -> North ))
return true;
// ...
return false;
}