有以下程序: #include<iostream> using namespace std; #definePl 3.14 Class Point private: int x,y; public: Point(int a,int b) X=a; y:b; int getx() <return x; int gety() return y;; class Circle:public Point private: int r; public: Circle(int a,int b,int c):Point(a,b) r=c; int getr() return r; double area() return PI*r*r; int main() Circle c1(5,7,10); cout<<c1.area()<<endl; return 0; 程序执行后的输出结果是( )。