#include<bits/stdc++.h> using namespace std; int main(){ double pai=3.1415926; int r1=1,r2=3,r3=5,r4=7,r5=9; cout<<pai*r1*r1<<endl; cout<<pai*r2*r2<<endl; cout<<pai*r3*r3<<endl; cout<<pai*r4*r4<<endl; cout<<pai*r5*r5<<endl; return 0; }