#include<bits/stdc++.h> using namespace std; int main() { const double PI=3.1415926; int r; double c,s; cin>>r; c=PI*2*r; s=PI*r*r; cout<<fixed<<setprecision(2)<<s<<endl; cout<<fixed<<setprecision(2)<<c<<endl; return 0; } /************************************************************** Problem: 1005 User: dengyuanyan Language: C Result: Compile Error ****************************************************************/