Item 1-point-circle-cylinder Group Design (1)

Questions and codes:

/* *copyright (c) 2016, Yantai University School of computer *all rights reserved. * File name: Zwj.cpp *:    Zhang Weijing * Completion Date: May 4, 2016 * version number: v1.0 * * Problem Description: Follow the prompts, starting from the base class gradually complete the point--circle--cylinder class family design. * Input Description: * Program output: */#include <iostream>using namespace Std;class point{public: Point    (Double a=0,double b=0);    void Show_point ();    Double Getx () {return x;}    Double Gety () {return y;} Protected:    double X;    Double y;}; Point::P oint (double a,double b) {    x=a;    Y=b;} The coordinates of void Point::show_point () {    cout<< "point are:" <<x<< "," <<Y<<ENDL;} int main () {point    P1;    P1.show_point ();    return 0;}

Operation Result:

Summary of Knowledge points:

Derived class constructor: the constructor for the ① base class is not inherited, and its constructor is declared in the derived class. When you define a constructor, you only need to initialize the new members of the class, initialize the inherited base class members, or automatically call the base class constructor to complete the ②. ③ to ensure that the constructors required by the derived class are defined in the base class.

Learning experience:

Item 1-point-circle-cylinder Group Design (1)