类.txt

钱能主编 C++程序设计教程（第一版） 该书习题的答案代码

//**************************
//**      ch11_1.cpp      **
//**************************
#include <iostream.h>

class Tdate
{
public:
	void Set(int m,int d,int y)  //set the date
	{
		month=m; day=d; year=y;
	}

	int IsLeapYear()
	{
		return (year%4==0&&year%100!=0)||(year%400==0);
	}

	void Print()
	{
		cout<<month<<"/"<<day<<"/"<<year<<endl;
	}
private:
	int month;
	int day;
	int year;
};

void main()
{
	Tdate a;
	a.Set(2,14,2005);
	a.Print();
	if(a.IsLeapYear())
		cout<<"this is a leap year."<<endl;
	else 
		cout<<"It's not a leap year."<<endl;
}

//**************************
//**      ch11_2.cpp      **
//**************************
//用指针调用成员函数
#include <iostream.h>
#include "Tdate.h"

void someFunc(Tdate* pS)
{
	pS->Print();
	if(pS->IsLeapYear())
		cout<<"oh, this is a leap year!"<<endl;
	else
		cout<<"oh..., it's not a leap year..."<<endl;
}

void main()
{
	Tdate a;
	a.Set(2,14,2005);
	someFunc(&a);
}

//**************************
//**      ch11_3.cpp      **
//**************************
//用引用传递来访问成员函数
#include <iostream.h>
#include "Tdate.h"

void someFunc(Tdate &rS)
{
	rS.Print();
	if(rS.IsLeapYear())
		cout<<"oh, this is a leap year!"<<endl;
	else
		cout<<"oh..., it's not a leap year..."<<endl;
}

void main()
{
	Tdate a;
	a.Set(2,14,2000);
	someFunc(a);
}

//**************************
//**      ch11_5.cpp      **
//**************************
#include <iostream.h>
#include <math.h>

class Point
{
public:
	void Set(double ix,double iy)
	{
		x=ix;
		y=iy;
	}

	double xOffset()
	{
		return x;
	}

	double yOffset()
	{
		return y;
	}

	double angle()
	{
		return (180/3.14159)*atan2(y,x);
	}

	double radius()
	{
		return sqrt(x*x+y*y);
	}

protected:
	double x;
	double y;
};

void main()
{
	Point p;
	double x,y;
	while(1)
	{
		cout<<"Enter x and y:"<<endl;
		cin>>x>>y;
		if(x<0)
			break;
		p.Set(x,y);
		cout<<"angle = "<<p.angle()
			<<",radius = "<<p.radius()
			<<",x offset = "<<p.xOffset()
			<<",y offset = "<<p.yOffset()<<endl;
	}
}
		
//**************************
//**      point2.cpp      **
//**************************
#include <math.h>

class Point
{
public:
	void Set(double ix,double iy)  //interface
	{
		a=atan2(iy,ix);
		r=sqrt(ix*ix+iy*iy);
	}

	double xOffset()  //interface  
	{
		return r * cos(a);
	}

	double yOffset()  //interface
	{
		return r * sin(a);
	}

	double angle()  //interface
	{
		return (180/3.14159)*a;
	}

	double radius()  //interface
	{
		return r;
	}

protected:
	double a;
	double r;
};