Thread: returning error on if/else in function

i overloaded the operator '-' to subtract 2 Distances. i dont want to accept negative distance so how do i exit the function? i tried "return -1;" but the return type is of type Distance. do i have to do the error checking in main?

Code:

Distance Distance::operator - (Distance d2) const	//return difference
{
	int f = feet - d2.feet;	//subtract feet
	float i = inches - d2.inches;	//subtract inches

	if(i < 0)
	{
		--f;
		i = 12 - (i * -1);
	}

	if(f < 0)
	{
		cout << "Error:	Negative Distance." << endl;        //this line doesnt print for some reason
		return Distance(0,0.0);
	}
	else
		return Distance(f,i);
}