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