oj(二）g

//小慧把手机掉了，着急的她想让你帮她找到，她的手机是很高级的，离开主人一定时间后就会发射固定频率的电磁波。//现在你有一个仪器可以接受电磁波并能确定手机坐标，请你编程来确定小慧和手机的距离。////Input//4个double型的数，前两个是手机的坐标，后两个是小慧的坐标。////Output//小慧与手机的距离。（保留两位小数）#include <iostream>#include <cstdio>#include <cmath>#include <iomanip>using namespace std;class Point{public:    Point(double a=0,double b=0,double c=0,double d=0):x1(a),y1(b),x2(c),y2(d) {}    void  input();    friend void output(Point &);private:    double x1;    double y1;    double x2;    double y2;};//*************void  Point::input(){    cin>>x1>>y1>>x2>>y2;}void output(Point &p){    cout<<fixed<<setprecision(2);    cout<<"There are ";    cout<<sqrt((p.x1-p.x2)*(p.x1-p.x2)+(p.y1-p.y2)*(p.y1-p.y2));    cout<<" meters between xiaohui and her phone."<<endl;}//以下代码会自动添加到程序的末尾int main(){    Point p1;    p1.input();    output(p1);    return 0;}

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