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

namespace Competitive_Programming
{
    class MainClass
    {
        Scanner sc;
        StringBuilder res;
        const long MOD = (long)1e9 + 7;
        static void Main(string[] args)
        {
            new MainClass().solve();
        }
        
        void solve()
        {
            sc = new Scanner();
            res = new StringBuilder();

            long N = sc.NextLong();
            res.Append((N % 4 == 3 ? "X" : "O"));

            Console.WriteLine(res);
            res.Clear();
        }
        int[] grundy;
        int dfs(int now)
        {
            if (grundy[now] != -1)
            {
                return grundy[now];
            }
            HashSet<int> se = new HashSet<int>();
            for (int i = now - 1; i >= 0; i--)
            {
                se.Add(dfs(i));
            }
            int n = 0;
            while (se.Contains(n))
            {
                n++;
            }
            return grundy[now] = n;
        }
    }
    
    class Scanner
    {
        Queue<string> buf;
        public Scanner()
        {
            buf = new Queue<string>();
        }
        private void GetBuf()
        {
            while (buf.Count == 0)
            {
                string[] stringArray = Console.ReadLine().Split(' ');
                if (stringArray.Length == 0 || stringArray[0] == "")
                {
                    continue;
                }
                foreach (string e in stringArray)
                {
                    buf.Enqueue(e);
                }
            }
        }
        public int NextInt()
        {
            return int.Parse(this.Next());
        }
        public long NextLong()
        {
            return long.Parse(this.Next());
        }
        public double NextDouble()
        {
            return double.Parse(this.Next());
        }
        public string Next()
        {
            this.GetBuf();
            return buf.Dequeue();
        }
    }
}