Abstract Base Classes: Syntax

virtual char *print_sex(void) = 0;

};

class female : person {

virtual char *print_sex(void) { cout << “I’m a female\n”; };

};

class male : person {

virtual char *print_sex(void) { cout << “I’m a male\n”; }

};

person *people[3];

people[0] = new person; // compile-time error!

people[1] = new female; // OK

people[2] = new male; // OK

for (int i = 0; i < 3; i++)

people[i]->print_sex();