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

namespace CSharp
{
    static class Program
    {
        static IEnumerable<string> EnumerateLunlunNumbers()
        {
            StringBuilder sb = new StringBuilder("0");

            while (true)
            {
                int index = sb.Length - 1;
                while (index >= 0)
                {
                    if (++sb[index] >= '0' + 10 || (index > 0 && Abs(sb[index - 1] - sb[index]) > 1))
                    {
                        index--;
                    }
                    else
                    {
                        break;
                    }
                }

                if (index < 0)
                {
                    int currentLength = sb.Length;
                    sb.Clear();
                    sb.Append('1').Append('0', currentLength);
                }
                else
                {
                    while (++index < sb.Length)
                    {
                        sb[index] = (char)Max(sb[index - 1] - 1, '0');
                    }
                }

                yield return sb.ToString();
            }
        }

        static void Main(string[] args)
        {
            int k = ReadInt();
            string ans = EnumerateLunlunNumbers().ElementAt(k - 1);
            Console.WriteLine(ans);
        }

        #region Helpers

        static int[] ReadIntArray() => Console.ReadLine().Split().Select(s => int.Parse(s)).ToArray();
        static long[] ReadLongArray() => Console.ReadLine().Split().Select(s => long.Parse(s)).ToArray();

        static int[] ReadLineIntArray(int count) => Enumerable.Repeat(0, count).Select(_ => int.Parse(Console.ReadLine())).ToArray();
        static long[] ReadLineLongArray(int count) => Enumerable.Repeat(0, count).Select(_ => long.Parse(Console.ReadLine())).ToArray();

        static string ReadString() => Console.ReadLine();
        static int ReadInt() => int.Parse(Console.ReadLine());
        static long ReadLong() => long.Parse(Console.ReadLine());

        static void ReadInt(out int first)
        {
            var array = ReadIntArray();
            first = array[0];
        }

        static void ReadInt(out int first, out int second)
        {
            var array = ReadIntArray();
            first = array[0];
            second = array[1];
        }

        static void ReadInt(out int first, out int second, out int third)
        {
            var array = ReadIntArray();
            first = array[0];
            second = array[1];
            third = array[2];
        }

        static void ReadInt(out int first, out int second, out int third, out int fourth)
        {
            var array = ReadIntArray();
            first = array[0];
            second = array[1];
            third = array[2];
            fourth = array[3];
        }

        static void ReadLong(out long first)
        {
            var array = ReadLongArray();
            first = array[0];
        }

        static void ReadLong(out long first, out long second)
        {
            var array = ReadLongArray();
            first = array[0];
            second = array[1];
        }

        static void ReadLong(out long first, out long second, out long third)
        {
            var array = ReadLongArray();
            first = array[0];
            second = array[1];
            third = array[2];
        }

        static void ReadLong(out long first, out long second, out long third, out long fourth)
        {
            var array = ReadLongArray();
            first = array[0];
            second = array[1];
            third = array[2];
            fourth = array[3];
        }

        static string YesNo(bool condition) => condition ? "Yes" : "No";
        static string YESNO(bool condition) => condition ? "YES" : "NO";

        #endregion
    }
}

Measured memory_bytes: 15316