c++ 嵌套类

[c++]代码库

#include <iostream>
using namespace std;
class rectangle
{
public:
	class point
	{
	public:
		void setx ( int x ) {itsx=x;}
		void sety ( int y ) {itsy=y;}
		int getx() const {return itsx;}
		int gety() const {return itsy;}
	private:
		int itsx;
		int itsy;
	};
	point GetUpLeft() const {return upleft;}
	point GetLowLeft() const {return lowerleft;}
	point GetUpRight() const {return upright;}
	point GetLowRight() const {return lowerright;}

	rectangle ( int top,int left,int bottom,int right );
	~rectangle() {}

	int GetTop() const {return Top;}
	int GetLeft() const {return Left;}
	int GetBottom() const {return Bottom;}
	int GetRight() const {return Right;}

	void SetUpLeft() {upleft.setx ( Left ); upleft.sety ( Top );}
	void SetLowLeft() {lowerleft.setx ( Left ); lowerleft.sety ( Bottom );}
	void SetUpRight() {upright.setx ( Right ); upright.sety ( Top );}
	void SetLowRight() {lowerright.setx ( Right ); lowerright.sety ( Bottom );}

	void SetTop ( int top ) {Top=top;}
	void SetLeft ( int left ) {Left=left;}
	void SetRight ( int right ) {Right=right;}
	void SetBottom ( int bottom ) {Bottom=bottom;}

	int GetArear() const {int width=Right-Left; int height=Bottom-Top; return ( width*height );}

private:
	point upleft;
	point lowerleft;
	point upright;
	point lowerright;

	int Top;
	int Left;
	int Bottom;
	int Right;
};
rectangle::rectangle ( int top,int left,int bottom,int right )
{
	Top=top;
	Left=left;
	Bottom=bottom;
	Right=right;

	upleft.setx ( Left );
	upleft.sety ( Top );

	upright.setx ( Right );
	upright.sety ( Top );

	lowerright.setx ( Right );
	lowerright.sety ( Bottom );

	lowerleft.setx ( Left );
	lowerleft.sety ( Bottom );
}
class point
{
public:
	int GetArear ( rectangle &rec ) {return rec.GetArear();}
};

int main()
{
	rectangle date ( 40,50,60,80 );
	cout<<"左边为："<<date.GetLeft() <<endl;
	cout<<"下边为："<<date.GetBottom() <<endl;
	cout<<"左下的X坐标为："<<date.GetLowLeft().getx() <<endl;
	cout<<"左下的y坐标为："<<date.GetLowLeft().gety() <<endl;
	cout<<"矩形面积为:"<<date.GetArear() <<endl;
	cout<<"重新设置Left和Bottom值"<<endl;
	date.SetLeft ( 0 );
	date.SetBottom ( 100 );
	date.SetLowLeft();
	cout<<"左边为："<<date.GetLeft() <<endl;
	cout<<"下边为："<<date.GetBottom() <<endl;
	cout<<"左下的X坐标为："<<date.GetLowLeft().getx() <<endl;
	cout<<"左下的y坐标为："<<date.GetLowLeft().gety() <<endl;
	point pt;
	cout<<"矩形面积为:"<<pt.GetArear ( date ) <<endl;
	system ( "pause" );
}