首页 > 代码库 > Problem D: 平面上的点和线——Point类、Line类 (IV)

Problem D: 平面上的点和线——Point类、Line类 (IV)

Description

在数学上,平面直角坐标系上的点用X轴和Y轴上的两个坐标值唯一确定,两点确定一条线段。现在我们封装一个“Point类”和“Line类”来实现平面上的点的操作。
根据“append.cc”,完成Point类和Line类的构造方法和show()方法,输出各Line对象和Point对象的构造和析构次序。
接口描述:
Point::show()方法:按格式输出Point对象。
Line::show()方法:按格式输出Line对象。

Input

输入的第一行为N,表示后面有N行测试样例。

每行为两组坐标“x,y”,分别表示线段起点和终点的x坐标和y坐标,两组坐标间用一个空格分开,x和y的值都在double数据范围内。

Output

输出为多行,每行为一条线段,起点坐标在前终点坐标在后,每个点的X坐标在前,Y坐标在后,Y坐标前面多输出一个空格,用括号包裹起来。输出格式见sample。
C语言的输入输出被禁用。

Sample Input

4 0,0 1,1 1,1 2,3 2,3 4,5 0,1 1,0

Sample Output

Point : (1, -2) is created. Point : (2, -1) is created. Point : (0, 0) is created. Point : (0, 0) Point : (0, 0) is created. Point : (0, 0) is created. Line : (0, 0) to (0, 0) is created. Point : (0, 0) is created. Point : (0, 0) is created. Line : (0, 0) to (0, 0) is created. Point : (0, 0) is created. Point : (0, 0) is created. Line : (0, 0) to (0, 0) is created. Point : (0, 0) is created. Point : (0, 0) is created. Line : (0, 0) to (0, 0) is created. ========================= Line : (0, 0) to (1, 1) ========================= Line : (1, 1) to (2, 3) ========================= Line : (2, 3) to (4, 5) ========================= Line : (0, 1) to (1, 0) ========================= Point : (1, -2) is copied. Point : (2, -1) is copied. Line : (1, -2) to (2, -1) is created. Point : (1, -2) is copied. Point : (0, 0) is copied. Line : (1, -2) to (0, 0) is created. Point : (2, -1) is copied. Point : (0, 0) is copied. Line : (2, -1) to (0, 0) is created. Point : (0, 0) is copied. Point : (2, -1) is copied. Line : (0, 0) to (2, -1) is created. Line : (1, -2) to (2, -1) Line : (1, -2) to (0, 0) Line : (2, -1) to (0, 0) Line : (0, 0) to (2, -1) Line : (0, 0) to (2, -1) is erased. Point : (2, -1) is erased. Point : (0, 0) is erased. Line : (2, -1) to (0, 0) is erased. Point : (0, 0) is erased. Point : (2, -1) is erased. Line : (1, -2) to (0, 0) is erased. Point : (0, 0) is erased. Point : (1, -2) is erased. Line : (1, -2) to (2, -1) is erased. Point : (2, -1) is erased. Point : (1, -2) is erased. Line : (0, 1) to (1, 0) is erased. Point : (1, 0) is erased. Point : (0, 1) is erased. Line : (2, 3) to (4, 5) is erased. Point : (4, 5) is erased. Point : (2, 3) is erased. Line : (1, 1) to (2, 3) is erased. Point : (2, 3) is erased. Point : (1, 1) is erased. Line : (0, 0) to (1, 1) is erased. Point : (1, 1) is erased. Point : (0, 0) is erased. Point : (0, 0) is erased. Point : (2, -1) is erased. Point : (1, -2) is erased.

HINT

Append Code

append.cc,
int main()
{
    char c;
    int num, i;
    double x1, x2, y1, y2;
    Point p(1, -2), q(2, -1), t;
    t.show();
    std::cin>>num;
    Line line[num];
    for(i = 0; i < num; i++)
    {
        std::cout<<"=========================\n";
        std::cin>>x1>>c>>y1>>x2>>c>>y2;
        line[i].SetLine(x1, y1, x2, y2);
        line[i].show();
    }
    std::cout<<"=========================\n";
    Line l1(p, q), l2(p, t), l3(q, t), l4(t, q);
    l1.show();
    l2.show();
    l3.show();
    l4.show();
}
 
代码
#include <iostream>
 
using namespace std;
 
class Point
{
    double x,y;
    friend class Line;
    public:
    Point(double xx=0,double yy=0):x(xx),y(yy)
    {
        cout<<"Point : ("<<x<<", "<<y<<") is created."<<endl;
    }
    ~Point()
    {
        cout<<"Point : ("<<x<<", "<<y<<") is erased."<<endl;
    }
    void show()
    {
        cout<<"Point : ("<<x<<", "<<y<<")"<<endl;
    }
    Point(const Point  & pl )
    {
        x=pl.x;
        y=pl.y;
        cout<<"Point : ("<<x<<", "<<y<<") is copied."<<endl;
    }
};
class Line
{
    Point p1,p2;
friend class Point;
    public:
        Line(double x1=0,double x2=0,double x3=0,double x4=0):p1(x1,x2),p2(x3,x4)
        {
            cout<<"Line : ("<<x1<<", "<<x2<<") to ("<<x3<<", "<<x4<<") is created."<<endl;
        }
        Line(Point &p,Point &q):p1(p),p2(q)
        {
            cout<<"Line : ("<<p1.x<<", "<<p1.y<<") to ("<<p2.x<<", "<<p2.y<<") is created."<<endl;
        }
        ~Line()
        {
            cout<<"Line : ("<<p1.x<<", "<<p1.y<<") to ("<<p2.x<<", "<<p2.y<<") is erased."<<endl;
        }
        void show()
        {
            cout<<"Line : ("<<p1.x<<", "<<p1.y<<") to ("<<p2.x<<", "<<p2.y<<")"<<endl;
        }
        void SetLine(double a,double b,double c,double d)
        {
            p1.x=a;
            p1.y=b;
            p2.x=c;
            p2.y=d;
        }
};
int main()
{
    char c;
    int num, i;
    double x1, x2, y1, y2;
    Point p(1, -2), q(2, -1), t;
    t.show();
    std::cin>>num;
    Line line[num];
    for(i = 0; i < num; i++)
    {
        std::cout<<"=========================\n";
        std::cin>>x1>>c>>y1>>x2>>c>>y2;
        line[i].SetLine(x1, y1, x2, y2);
        line[i].show();
    }
    std::cout<<"=========================\n";
    Line l1(p, q), l2(p, t), l3(q, t), l4(t, q);
    l1.show();
    l2.show();
    l3.show();
    l4.show();
}
 

Problem D: 平面上的点和线——Point类、Line类 (IV)