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。
Line::SetLine(double, double, double, double)方法：设置Line对象起点的x,y坐标（第一个和第二参数）和终点的x,y坐标（第三个和第四个坐标），并返回本对象
Line::SetLine(const Point &, const Point &)方法：设置Line对象的起点（第一个参数）和终点（第二个坐标），并返回本对象
Line::SetLine(const Line&)方法：设置Line对象，复制参数的坐标，并返回本对象
Line::readLine()方法：从标准输入上读入坐标，格式见Sample
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 : (1, -2) is copied.
Point : (2, -1) is copied.
Line : (1, -2) to (2, -1) is copied.
Line : (1, -2) to (2, -1)
Line : (1, -2) to (2, -1)
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 (2, -1) is erased.
Point : (2, -1) 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.
AC代码
#include <iostream>
using namespace std;
class Point {
friend class Line;
private:
double x,y;
public:
void setPoint(double a,double b){x=a;y=b;}
Point():x(0),y(0) {cout << "Point : (" << x << ", " << y << ") is created.\n";}
Point(double x1, double y1) : x(x1), y(y1) {cout << "Point : (" << x << ", " << y << ") is created.\n";}
void show() const {cout << "Point : (" << x << ", " << y << ")\n";}
Point(const Point &p) :x(p.x), y(p.y) {cout << "Point : (" << x << ", " << y << ") is copied.\n";}
~Point(){cout << "Point : (" << x << ", " << y << ") is erased.\n";}
};
class Line {
friend class Point;
private:
Point p, q;
public:
Line():p(0, 0), q(0, 0){
cout << "Line : (" << p.x << ", " << p.y << ") to (" << q.x << ", " << q.y << ") is created.\n";
}
Line(Point &p1, Point &q1):p(p1), q(q1) {
cout << "Line : (" << p.x << ", " << p.y << ") to (" << q.x << ", " << q.y << ") is created.\n";
}
~Line(){
cout << "Line : (" << p.x << ", " << p.y << ") to (" << q.x << ", " << q.y << ") is erased.\n";
}
Line(double x1, double y1, double x2, double y2): p(x1, y1), q(x2, y2){
cout << "Line : (" << p.x << ", " << p.y << ") to (" << q.x << ", " << q.y << ") is created.\n";
}
void show() const {cout << "Line : (" << p.x << ", " << p.y << ") to (" << q.x << ", " << q.y << ")\n";}
Line& setLine(double x1, double y1, double x2, double y2);
void readLine();
Line& setLine(const Point &, const Point &);
Line& setLine(const Line&);
Line(const Line& L): p (L.p) , q ( L.q) {
cout << "Line : (" << p.x << ", " << p.y << ") to (" << q.x << ", " << q.y << ") is copied.\n";
}
};
void Line::readLine() {
char c;
double x1, y1, x2, y2;
cin >> x1 >> c >> y1 >> x2 >> c >> y2;
p.setPoint(x1, y1);
q.setPoint(x2, y2);
}
Line& Line::setLine(const Point &p1, const Point &q1) {
p = p1;
q = q1;
return *this;
}
Line& Line::setLine(double x1, double y1, double x2, double y2) {
p.x = x1;
p.y = y1;
q.x = x2;
q.y = y2;
return *this;
}
Line& Line::setLine(const Line &L) {
p = L.p;
q = L.q;
return *this;
}
int main()
{
int num, i;
Point p(1, -2), q(2, -1), t;
t.show();
std::cin>>num;
Line line[num];
for(i = 0; i < num; i++)
{
line[i].readLine();
line[i].show();
}
Line l1(p, q), l2(p,t), l3(q,t), l4(l1);
l1.show();
l2.setLine(l1).show();
l3.show();
l4.setLine(t,q).show();
}
