#include<bits/stdc++.h> using namespace std; int main(){ double a,b,c,d,e; cin>>a>>b>>c>>d>>e; cout<<a*a*3.1415926<<endl<<b*b*3.1415926<<endl<<c*c*3.1415926<<endl<<d*d*3.1415926<<endl<<e*e*3.1415926; }