In the following code, is there a way to make extint *smaller point to both variables of extint type and const extint type? 
extint extint::operator+ (const extint &b)
{
    extint result;
    int sum;
    extint* smaller = (num.size() < b.num.size()) ? this : &b;
    //do stuff
    return result;
}
Please advise.
 
    