Problem B: 平面上的点和线——Point类、Line类 (II)
Problem B: 平面上的点和线——Point类、Line类 (II)
Time Limit: 1 Sec Memory Limit: 128 MBSubmit: 5701 Solved: 3888
[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。
Sample Input
4 0,0 1,1 1,1 2,3 2,3 4,5 0,1 1,0
Sample Output
Point : (0, 0) Line : (0, 0) to (1, 1) is created. Line : (0, 0) to (1, 1) Line : (0, 0) to (1, 1) is erased. Line : (1, 1) to (2, 3) is created. Line : (1, 1) to (2, 3) Line : (1, 1) to (2, 3) is erased. Line : (2, 3) to (4, 5) is created. Line : (2, 3) to (4, 5) Line : (2, 3) to (4, 5) is erased. Line : (0, 1) to (1, 0) is created. Line : (0, 1) to (1, 0) Line : (0, 1) to (1, 0) is erased. Line : (1, -2) to (2, -1) is created. Line : (1, -2) to (0, 0) is created. Line : (2, -1) to (0, 0) is created. 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. Line : (2, -1) to (0, 0) is erased. Line : (1, -2) to (0, 0) is erased. Line : (1, -2) to (2, -1) is erased.
#include <iostream> using namespace std; class Point { public: double st,ed; Point(double stt,double edd):st(stt),ed(edd){} Point():st(0),ed(0){} void show(){cout<<"Point : ("<<st<<", "<<ed<<")"<<endl;} double x()const{return st;} double y()const{return ed;} } ; class Line { public: Point st_,ed_; 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;} Line(const Point &stt,const Point &edd):st_(stt.x(),stt.y()),ed_(edd.x(),edd.y()){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;} }; 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; for(i = 1; i <= num; i++) { std::cin>>x1>>c>>y1>>x2>>c>>y2; Line line(x1, y1, x2, y2); line.show(); } Line l1(p, q), l2(p, t), l3(q, t), l4(t, q); l1.show(); l2.show(); l3.show(); l4.show(); }