#include <bits/stdc++.h> using namespace std; double pai = 3.14159; int main() { double r; cin>>r; double a= 2r; double b= 2pair; double c= pair*r; printf("%.4lf %.4lf %.4lf\n",a,b,c); return 0; }

#include <bits/stdc++.h> using namespace std; int main() { double a,b; cin >> a >> b ; printf("%.9lf",a/b); return 0; }