SpeedInfo

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SpeedInfo
{
class SpeedInfo
{
    static void Main(string[] args)
    {
        double speed = Double.Parse(Console.ReadLine());

        if (speed > 1000)
        {
            Console.WriteLine("extremely fast");
        }
        else if (speed <= 1000 && speed > 150)
        {
            Console.WriteLine("ultra fast");
        }
        else if (speed <= 150 && speed > 50)
        {
            Console.WriteLine("fast");
        }
        else if (speed <= 50 && speed > 10)
        {
            Console.WriteLine("average");
        }
        else if (speed <= 10 && speed > 0)
        {
            Console.WriteLine("slow");
        }
        else if (speed <0)
        {
            Console.WriteLine("slow");
        }
        }
    }
}