Problem E: 平面上的点和线——Point类、Line类 (V)
Problem E: 平面上的点和线——Point类、Line类 (V)
Time Limit: 1 Sec Memory Limit: 128 MBSubmit: 8942 Solved: 4499
[Submit][Status]
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.
#include <iostream> using namespace std; class Point { friend class Line; private: double st,ed; public: Point():st(0),ed(0){cout << "Point : (" <<st<< ", " <<ed<<") is created." << endl;} Point(double stt ,double edd ):st(stt),ed(edd){cout << "Point : (" <<st<< ", " <<ed<<") is created." << endl;} Point (const Point &p) { st = p.st; ed= p.ed; cout << "Point : (" << st<< ", " << ed<<") is copied." << endl; } double x() const {return st;} double y() const {return ed;} void show() {cout << "Point : (" <<st<< ", "<<ed<< ")" <<endl;} ~Point () {cout << "Point : (" <<st<< ", " <<ed <<") is erased." << endl;} }; class Line { friend class Point; private : Point st_,ed_; public: Line():st_(0,0),ed_(0,0) { cout << "Line : (" << st_.x() << ", " << st_.y()<< ") to (" <<ed_.x() <<", " << ed_.y() << ")" << " is created." << endl; } Line( Point &sst, Point &eed):st_(sst),ed_(eed) { cout << "Line : (" << st_.x() << ", " << st_.y()<< ") to (" <<ed_.x() <<", " << ed_.y() << ")" << " is created." << endl;} Line(double x1,double y1,double x2,double y2):st_(x1,y1),ed_(x2,y2) { cout << "Line : (" << st_.x() << ", " << st_.y()<< ") to (" <<ed_.x() <<", " << ed_.y() << ")" << " is created." << endl; } void show() const {cout << "Line : (" << st_.x() << ", " << st_.y()<< ") to (" <<ed_.x() <<", " << ed_.y() << ")" <<endl; } ~Line() { cout << "Line : (" << st_.x() << ", " << st_.y()<< ") to (" <<ed_.x() <<", " << ed_.y() << ")" << " is erased." << endl;} Line(const Line &l):st_(l.st_),ed_(l.ed_) {cout << "Line : (" << st_.x() << ", " << st_.y()<< ") to (" <<ed_.x() <<", " << ed_.y() << ")" << " is copied." <<endl;} Line setLine(double x1,double y1,double x2,double y2) { st_.st=x1; st_.ed=y1; ed_.st=x2; ed_.ed=y2; return *this;} Line &setLine(const Point &p ,const Point &q) { st_=p; ed_=q; return *this; } Line &setLine(const Line &p) { st_=p.st_; ed_=p.ed_; return *this; } void readLine() { double x1,y1,x2,y2; char in; cin>>x1>>in>>y1>>x2>>in>>y2; st_.st=x1; st_.ed=y1; ed_.st=x2; ed_.ed=y2; }}; 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(); }