#include<iostream>
#include<string>
using namespace std;
int main()
{
    string shape;
    float radius,width,height,area;
    if(radius<=0||width<=0||height<=0){
        cout<<"Invalid input";
        return 0;
    }
    if(shape=="circle"){
        area=(22/7)*radius*radius;
        cout<<area;
        return 0;
    }
    else if(shape=="rectangle"){
        area=width*height;
        cout<<area;
        return 0
    }
    else{
        cout<<"Invalid shape";
        return 0;
    }
}