def biebao(n,time): order=list(range(1,n+1)) order.sort(key=lambda x:time[x-1]) total_time=0 curr_time=0 for i in range(n-1): curr_time+=time[order[i]-1] total_time+=curr_time avg_time=total_time/n return order,avg_time n=int(input()) time=list(map(int,input().split(" "))) order,avg_time=biebao(n,time) print(" ".join(map(str,order))) print("{:.2f}".format(avg_time))