C++面向对象程序的设计第六章课后习题答案(第2版—谭浩强)

1、第六章课后习题答案第二版谭浩强1:/xt6-1/cpp#include <iostream> /如用 VC+应改为：#include <iosttram.h>using namespace std; / 如用 VC+应取消此行#include "cylinder.h"#include "point.cpp"#include "circle.cpp"#include "cylinder.cpp"int main()Cylinder cy1(3.5,6.4,5.2,10);cout<<

2、;"noriginal cylinder:nx="<<cy1.getX()<<", y="<<cy1.getY()<<", r="<<cy1.getRadius()<<", h="<<cy1.getHeight()<<"narea="<<cy1.area()<<", volume="<<cy1.volume()<<endl;cy1.s

3、etHeight(15);cy1.setRadius(7.5);cy1.setPoint(5,5);cout<<"nnew cylinder:n"<<cy1;Point &pRef=cy1;cout<<"npRef as a point:"<<pRef;Circle &cRef=cy1;3: 解法#include <iostream>using namespace std;class Pointpublic:Point(float a,float b):x(a),y(b)Poin

4、t()cout<<"executing Point destructor"<<endl; private:float x;float y;class Circle:public Pointpublic:Circle(float a,float b,float r):Point(a,b),radius(r) Circle()cout<<"executing Circle destructor"<<endl; private:float radius;int main()3：解法二#include <io

5、stream>using namespace std;class Pointpublic:Point(float a,float b):x(a),y(b)Point()cout<<"executing Point destructor"<<endl;private:float x;float y;class Circle:public Pointpublic:Circle(int a,int b,int r):Point(a,b),radius(r)Circle()cout<<"executing Circle destr

6、uctor"<<endl; private:float radius;int main()Point *p=new Circle(2.5,1.8,4.5);Circle *pt=new Circle(2.5,1.8,4.5);delete pt;return 0;3：解法三#include <iostream>using namespace std;class Pointpublic:Point(float a,float b):x(a),y(b)virtual Point()cout<<"executing Point destruct

7、or"<<endl; private:float x;float y;class Circle:public Pointpublic:Circle(float a,float b,float r):Point(a,b),radius(r)virtual Circle()cout<<"executing Circle destructor"<<endl; private:float radius;void main()结构函数定义虚函数半径结构函数定义虚函数4：#include <iostream>using name

8、space std;/ 定义抽象基类 Shapeclass Shapepublic:virtual double area() const =0; / 纯虚函数 ;/ 定义 Circle 类class Circle:public Shapepublic:Circle(double r):radius(r) /virtual double area() const return 3.14159*radius*radius; / protected:double radius;/;/ 定义 Rectangle 类class Rectangle:public Shapepublic:Rectangl

9、e(double w,double h):width(w),height(h)/virtual double area() const return width*height; / protected:double width,height;/宽与高class Triangle:public Shapepublic:Triangle(double w,double h):width(w),height(h)/结构函数virtual double area() const return 0.5*width*height;/定义虚函数protected:double width,height;/宽

10、与高/ 输出面积的函数void printArea(const Shape &s)cout<<s.area()<<endl;积/输出 s 的面int main()Circle circle(12.6); 类对象 circle/建立 Circlecout<<"area of circle ="printArea(circle);的面积/输出 circleRectangle rectangle(4.5,8.4);Rectangle 类对象 rectangle/建立cout<<"area of rectangle

11、="6 / 10printArea(rectangle);rectangle 的面积Triangle triangle(4.5,8.4); / cout<<"area of triangle =" printArea(triangle); / return 0;5：#include <iostream>using namespace std;/ 定义抽象基类 Shape class Shapepublic:virtual double area() const =0; ;/建立 Triangle 类对象输出 triangle 的面积/纯虚函

12、数输出结构函数定义虚函数半径/ 定义 Circle( 圆形) 类class Circle:public Shapepublic:Circle(double r):radius(r) /virtual double area() const return 3.14159*radius*radius; / protected:double radius;/;/ 定义 Square( 正方形 ) 类 class Square:public Shape public:Square(double s):side(s)/结构函数virtual double area() const return side

13、*side; /定义虚函数protected:double side;/ 定义 Rectangle( 矩形 ) 类class Rectangle:public Shapepublic:Rectangle(double w,double h):width(w),height(h) / virtual double area() const return width*height;/protected:double width,height; /结构函数定义虚函数宽与高;/ 定义 Trapezoid( 梯形 ) 类 class Trapezoid:public ShapeTrapezoid(dou

14、ble t,double b,double h):top(t),bottom(t),height(h) /结构函数virtual double area() const return 0.5*(top+bottom)*height; /定义虚函public:数protected:double top,bottom,height; / 底与高上底、下;/ 定义 Triangle( 三角形 ) 类class Triangle:public Shapepublic:Triangle(double w,double h):width(w),height(h) /结构函数virtual double a

15、rea()const return 0.5*width*height; /定义虚函数protected:double width,height;/宽与高int main()Circle circle(12.6); / 类对象 circleSquare square(3.5); / 类对象 square建立 Circle建立 SquareRectangle rectangle(4.5,8.4);/Rectangle 类对象 rectangleTrapezoid trapezoid(2.0,4.5,3.2); /Trapezoid 类对象 trapezoid建立建立Triangle triangle(4.5,8.4);Triangle 类对象/建立Shape *pt5=&circle,&squ