using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[] NMi => ReadLine().Split().Select(c => int.Parse(c) - 1).ToArray();
    static int[][] NMap(int n) => Enumerable.Repeat(0, n).Select(_ => NMi).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var k = NN;
        var bitmax = 16;
        var list = new List<string>();
        for (var b = 0; b < bitmax; ++b)
        {
            var tmp = b;
            var t = new List<char>();
            for (var i = 0; i < 4; ++i)
            {
                t.Add("NUPC"[i]);
                if (tmp % 2 == 1) t.AddRange(t);
                tmp >>= 1;
            }
            list.Add(string.Concat(t));
        }
        list.Sort();
        WriteLine(list[k - 1]);
    }
}