#include <iostream> #include <cstdio> #include <algorithm> using namespace std; double sum; long int n; long long int t[1001]; double ans; int main(int argc, const char * argv[]) { cin>>n; int x; for(int i=1;i<=n;i++) { cin>>x; t[i]=x*1001+i; } sort(t+1,t+1+n); for(int j=1;j<=n;j++) { cout<<t[j]%1001<<" "; sum+=t[j]/1001*(n-j); } cout<<endl; ans=sum/n; printf("%0.2lf",ans); return 0; }