[说明] 设计一个普通函数distance (Point &p1,Point &p2),用于计算p1和p2点之间的距离。本程序执行结果如下:(2,2)与(5,5)之间距离=4.24264 # include < iostream. h > # include < math. h > class Point int x, y; public: Point(int i, int j) (1) int getx( ) return x; int gety( ) return y; void disp( )