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

class Program
{
    public void Proc()
    {
        Reader.IsDebug = false;
        long num = long.Parse(Reader.ReadLine());
        long ans  = 0;
        long tmp = 0;
        if(num == 1) {
            Console.WriteLine(1);
            return;
        }
        if(num % 2 == 0) {
            tmp = (num / 2) * (num-1);
        } else
        {
            tmp = ((num-1) / 2) * num;
        }
        
        long tmp2 = Math.Min(tmp, num);
        tmp = Math.Max(tmp, num);
        while (tmp % tmp2 != 0)
        {
            long tmp3 = tmp % tmp2;
            tmp = tmp2;
            tmp2 = tmp3;
        }
        Console.WriteLine(tmp2);
    }

    public class Reader
    {
        public static bool IsDebug = true;
        private static String PlainInput = @"




2





 
";
        private static System.IO.StringReader Sr = null;
        public static string ReadLine()
        {
            if (IsDebug)
            {
                if (Sr == null)
                {
                    Sr = new System.IO.StringReader(PlainInput.Trim());
                }
                return Sr.ReadLine();
            }
            else
            {
                return Console.ReadLine();
            }
        }
        public static int[] GetInt(char delimiter = ' ', bool trim = false)
        {
            string inptStr = ReadLine();
            if (trim)
            {
                inptStr = inptStr.Trim();
            }
            string[] inpt = inptStr.Split(delimiter);
            int[] ret = new int[inpt.Length];
            for (int i = 0; i < inpt.Length; i++)
            {
                ret[i] = int.Parse(inpt[i]);
            }
            return ret;
        }
    }
    static void Main()
    {
        Program prg = new Program();
        prg.Proc();
    }
}