圆锥管螺纹数控加工方法.docx

习题点评—求多种图形的周长与面积
#ifndef SHAPE_H
#define SHAPE_H
#include <iostream>
#include <cmath>
using namespace std;
class shape
{
protected:
double ar,pe;
public:
double area() {ar=0;};
double perimeter() {pe=0;};
void display(){
cout<<"面积为:"<<ar<<endl;
cout<<"周长为:"<<pe<<endl;
}
};
#endif
#ifndef MULTISHAPE_H
#define MULTISHAPE_H
#include “”
class circle: public shape
{
double r;
public:
void area()
{
ar=r*r*;
}
void perimeter()
{
pe=2**r;
}
circle (double a):r(a){}
~ circle(){}
};
class rectangular :public shape
{
double a,b;
public:
void area()
{
ar=a*b;
}
void perimeter()
{
pe=2*(a+b);
}
rectangular (double x,double y):a(x),b(y){}
~ rectangular (){}
};
定义一个公共基类
多种图形继承自基类
class square: public shape
{
double a;
public:
void area()
{
ar=a*a;
}
void perimeter()
{
pe=4*a;
}
square (double x):a(x){}
~square(){}
};
class triangle: public shape
{
double a,b,c;
public:
void area()
{
double s=(a+b+c)/2;
ar=sqrt(s*(s-a)*(s-b)*(s-c));
}
void perimeter()
{
pe=a+b+c;
}
triangle (double x,double y,double z):a(x),b(y),c(z){}
~triangle(){}
};
#endif
多种图形继承自基类
#include ““
#include “”
void main()
{
circle a(5);
square b(5);
rectangular c(2,3);
triangle d(3,4,5);
();
();
();
();
();
();
();
();
();
();
();