The combined concept and example usage of classes in C language and C++

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Catalogue

Overview

Case

Summary

Overview

Composition refers to objects of another kind in one class as data members.

Case

Two points are connected into a straight line on the plane to find the length of the line and the coordinates of the midpoint of the line.

Request:

Base class: Dot

Derived class: Line (combined simultaneously)

Derived class Line inherits Dot data from the base class Dot, storing the midpoint coordinates of the line

The Line class adds two more Dot objects to store the coordinates of the two endpoints

Dot class:

# ifndef PROJECT5_DOT_H#define PROJECT5_DOT_H#include using namespace std;class Dot {public: double x, y; Dot (double a, double b): X (a), y (b) {}; void show () {cout