#include<iostream>
#include<cmath>
using namespace std;
class area{
    public:
    const double pi = 3.14159
    void show(float r){
        cout<<pi*pow(r,2);
    }
    void show(float a, float b){
        cout<<a*b;
    }
};
int main(){
    area obj;
    int n;
    cout<<"Enter value 1 or 2 for area of either circle or rectangle:  "<<endl;
    cin>>n;
    if (n==1){
        float r;
        cout<<"Enter radius:"<<endl;
        cin>>r;
        obj.show(r);
    }
    else if ( n == 2){
        float a,b;
        cout<<"Enter a,b values: "<<endl;
        cin>>a;
        cin>>b;
        obj.show(a,b);
    }
    else{
        cout<<"Invalid input";
    }
    return 0;
}