阅读程序，写出运行结果。
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库#include<iostream>
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库using namespace std;
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库#include<cmath>
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库class Point
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库{ public :
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 Point( float x, float y )
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 { a = x; b = y; cout<<"点( "<<a<<", "<<b<<" )"; }
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 friend double d( Point &A, Point &B )
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 { return sqrt((A.a-B.a)*(A.a-B.a)+(A.b-B.b)*(A.b-B.b)); }
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 private:
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 double a, b;
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库};
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库int main()
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库{ Point p1( 2, 3 );
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 cout << " 到";
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 Point p2( 4, 5 );
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 cout << "的距离是：" << d( p1,p2 ) << endl;
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库}
Y5t100150满分答卷(100150.com)-青少年编程等级考试及竞赛题库 
