#include<bits/stdc++.h> using namespace std; int main(){ int r; float c,s,pi=3.1415926; cin>>r; c=2*pi*r; s=pi*r*r; printf("%.2f\n%.2f",c,s); return 0; } /************************************************************** Problem: 1005 User: zhangchenhao Language: C++ Result: Wrong Answer ****************************************************************/