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

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            int count = 1;
            double sum = 0;
            while (sum<500)
            {
                sum =sum+Math.Pow(count,2);
                count++;
            }
            Console.WriteLine(count);
        }

    }
}