using System;
class Program
{
public static void Main(string[] args)
{
var inputStr = Console.ReadLine();
float input;
if(!float.TryParse(inputStr, out input))
return;
var result = input * 10;
if(result % 10 >=5)
result = (int)input + 1;
else
result = (int)input; Console.WriteLine(result);
}
}