1、/*定義一個圓類，聲明一個靜態數據成員和一個靜態成員函數，靜態數據成員表示圓的個數，定義對象時個數加1，西狗屎個數減1，靜態成員函數顯示靜態數據成員的值*/#include <iostream>using namespace std;class Circlepublic:Circle(float tr) r=tr ;countP+; Circle(Circle &p)r=p.r;countP+; static void GetP( ) cout<<" circle num="<<countP<<endl; Circle

2、()countP-; private:int r;static int countP;int Circle:countP=0; /給靜態數據成員countP初始化void main( )Circle A(4); A.GetP(); /*模擬商店一種貨物的購進和賣出情況，要求該種貨物以重量為單位成箱買賣，每箱的重量不相同，并且要求記錄目前庫存總重量和總價格。*/#include <iostream>using namespace std;class Goodspublic:Goods(float tprice,float tweight) unitPrice=tprice ; wei

3、ght=tweight;sumPrice+=unitPrice*weight;sumWeight+=weight;selFlag=0; void sell() selFlag=1; sumWeight-=weight;sumPrice-=unitPrice*weight;static void Show( )cout<<" sumPrice="<<sumPrice<<endl<<" sumWeight="<<sumWeight<<endl; private:float unitPri

4、ce,weight,selFlag;static float sumPrice,sumWeight;float Goods:sumPrice =0;float Goods:sumWeight=0; void main( )Goods A(4,5); A.Show (); A.sell ();A.Show(); /定義點類，并用兩個點構成一個矩形，求矩形的面積和周長#include<iostream>#include<cmath>using namespace std;class Point/Point類定義public:Point(int xx=0, int yy=0)

5、 X=xx;Y=yy;Point(Point &p);int GetX() return X;int GetY() return Y;friend class Rectangle;private:int X,Y;Point:Point(Point &p)/拷貝構造函數的實現X=p.X;Y=p.Y;/類的聚集class Rectangle/Distance類的定義public:/外部接口Rectangle(Point xp1, Point xp2);Rectangle(int x1,int y1,int x2,int y2);double Area() return length

6、*width;double RoundLength()return 2*(length+width);private:/私有數據成員Point p1,p2;/Point類的對象p1,p2double length,width;Rectangle:Rectangle(Point xp1, Point xp2):p1(xp1),p2(xp2) /類的聚集的構造函數length=abs(p1.X-p2.X);width=abs(p1.Y -p2.Y);Rectangle:Rectangle(int x1,int y1,int x2,int y2):p1(x1,y1),p2(x2,y2) length=abs(p1.X-p2.X);width=abs(p1.Y -p2.Y);/主函數void main()int x1,x2,y1,y2;cin>>x1>>y1>>x2>>y2;Point myp1(x1,y1),myp2(x2,y2);/定義Point類的對象Rectangle r1(myp1,myp2);/定義Distance類的對象cout<<"The Rectangel's area is: "<<r1.Area()<<endl; R