#include<bits/stdc++.h> using namespace std; int main() { int r; double pi=3.1415926,z,m; cin>>r; z=2*r*pi; m=r*r*pi; printf("%.2f\n%.2f",m,z); return 0; } /************************************************************** Problem: 1005 User: zhuangsongyu Language: C++ Result: Accepted Time:15 ms Memory:2072 kb ****************************************************************/