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);

}

}