#include <iostream>
#include <cmath>
using namespace std;
int main()
{
double r,h,a;
cout<<"enter the radius="<<endl;
cin>>r;
cout<<"enter the hight="<<endl;
cin>>h;
if (r==0 || h==0)
{
cout<<"invalid operation"<<endl;
}
if(r!=0 && h!=0)
{
a=(3.14*r*r*h)/3;
cout<<"the area="<<a<<endl;
}
system("pause");
return 0;
}