The role of inheritance and the method of initializing all the data in subclasses

1. Easy to expand the program so that it does not have to rewrite the entire program

code example

1#include <iostream>2#include <string>3 using namespacestd;4 classFather5 {6 protected:7     stringname;8     inttall;9  Public:TenFatherstringAinti); OneFather () {cout <<"construct base class \ n"; } A     voidPrint () {cout << name <<"height is"<< Tall <<"\ n"; } -~father () {cout <<"release base class object \ n"; } - }; the /*-------------is equivalent to the function of the original program-------------*/ -Father::father (stringAinti) - { -cout <<"\ n In the constructor of the base class \ n"; +Name =A; -Tall =i; + print (); Acout <<"leave the base class constructor \ n"; at } - classSon: PublicFather - { - Private: -     intweight; -  Public: inSonstringAintIintj); -     voidprint1 (); to~son () {cout <<"\ nthe subclass object is released \ n"; } + }; - /*--------is equivalent to adding new functionality to the original program functionality-----------*/ theSon::son (stringAintIintj) * { $Name =A;Panax NotoginsengTall =i; -cout <<"\ n in the subclass constructor \ n"; theWeight =J; + } A voidson::p rint1 () the { + father::p rint (); -cout <<"Weight:"<<weight; $ } $ intMain () - { -Son A ("Mike", the, the); the a.print1 (); -cout <<"it's over, \ n";Wuyi         return 0; the}

Run results

Programme II

code example

1#include <iostream>2#include <string>3 using namespacestd;4 classFather5 {6 protected:7     stringname;8     inttall;9  Public:TenFatherstringAinti); OneFather () {cout <<"construct base class \ n"; } A     voidPrint () {cout << name <<"height is"<< Tall <<"\ n"; } -~father () {cout <<"release base class object \ n"; } - }; the /*-------------is equivalent to the function of the original program-------------*/ -Father::father (stringAinti) - { -cout <<"\ n In the constructor of the base class \ n"; +Name =A; -Tall =i; + print (); Acout <<"leave the base class constructor \ n"; at } - classSon: PublicFather - { - Private: -     intweight; -  Public: inSonstringAintIintj); -     voidprint1 (); to~son () {cout <<"\ nthe subclass object is released \ n"; } + }; - /*--------is equivalent to adding new functionality to the original program functionality-----------*/ theSon::son (stringAintIintJ): Father (A,i)//the Difference * { $     //name = A;Panax Notoginseng     //tall = i; -cout <<"\ n in the subclass constructor \ n"; theWeight =J; + } A voidson::p rint1 () the { + father::p rint (); -cout <<"Weight:"<<weight; $ } $ intMain () - { -Son A ("Mike", the, the); the a.print1 (); -cout <<"it's over, \ n";Wuyi         return 0; the}

Results show

Clearly, scenario two is better.

The role of inheritance and the method of initializing all the data in subclasses