macOS what's wrong?! (c++)

[chris200x9]

whats wrong with this function

double CalculateShippingCharges( int pounds, int ounces )
{

while (ounces >= 16)
{
pounds++;

ounces - 16;
}
	cout << pounds;
	cout << ounces;
	
	return 0;
}

when I invoke it in main and run it instead of having any output it just says program exited normally

 

[chris200x9]

actually it just says session started and then doesnt end

 

[chris200x9]

omfg I'm retarded ok ignore this thread

 

[pilotError]

could it be:

ounces -= 16;