#include <algorithm>
#include <complex>
#include <cstdlib>
#include <ctime>
#include <time.h>
#include <iomanip>
#include <iostream>
#include <map>
#include <math.h>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>

using namespace std;
#define SAY_YES cout << "YES" << endl;
#define SAY_Yes cout << "Yes" << endl;
#define SAY_NO cout << "NO" << endl;
#define SAY_No cout << "No" << endl;
#define IFYES(TRUE_OR_FALSE)   \
    if (TRUE_OR_FALSE)         \
    {                          \
        cout << "YES" << endl; \
    }                          \
    else                       \
    {                          \
        cout << "NO" << endl;  \
    }
#define IFYes(TRUE_OR_FALSE)   \
    if (TRUE_OR_FALSE)         \
    {                          \
        cout << "Yes" << endl; \
    }                          \
    else                       \
    {                          \
        cout << "No" << endl;  \
    }
#define IFyes(TRUE_OR_FALSE)   \
    if (TRUE_OR_FALSE)         \
    {                          \
        cout << "yes" << endl; \
    }                          \
    else                       \
    {                          \
        cout << "no" << endl;  \
    }
#define DEBUG_OUTPUT_ARRAY(XXX, ONE)                            \
    for (int i = 0; i < (ONE); i++)                             \
    {                                                           \
        cout << "DEBUG: i = " << i << " -> " << XXX[i] << endl; \
    }
#define DEBUG_OUTPUT_ARRAY2(XXX, ONE, TWO)                             \
    for (int i = 0; i < (ONE); i++)                                    \
    {                                                                  \
        cout << "<<< i = " << i << " >>>" << endl;                     \
        for (int j = 0; j < (TWO); j++)                                \
        {                                                              \
            cout << "DEBUG: j = " << j << " -> " << XXX[i][j] << endl; \
        }                                                              \
    }
#define DEBUG_OUTPUT_ARRAY2_BOX(XXX, ONE, TWO) \
    for (int i = 0; i < (ONE); i++)            \
    {                                          \
        cout << i << "  ";                     \
        for (int j = 0; j < (TWO); j++)        \
        {                                      \
            cout << XXX[i][j] << " ";          \
        }                                      \
        cout << endl;                          \
    }

typedef pair<long long int, long long int> pll;


const long long int mod = 1000000007;
const long long int INF = 1e18;



long long int N,M,K,A[200200],sum=0,res=0;
long long int runrun[15][20]={{1,1,1,1,1,1,1,1,1,1}},number[20]={9};
int main()
{
    cout << fixed << setprecision(18);
    cin>>K;
    if(K<=9){
        cout<<K<<endl;
        return 0;
    }
    for(long long int i = 1; i < 13; i++){
        for(long long int j = 1; j <= 8; j++){
            runrun[i][j]+=runrun[i-1][j]+runrun[i-1][j-1]+runrun[i-1][j+1];

        }
        runrun[i][0]=runrun[i-1][0]+runrun[i-1][1];
        runrun[i][9]=runrun[i-1][9]+runrun[i-1][8];
        for(long long int j = 1; j <= 9; j++){
            number[i]+=runrun[i][j];
        }
        number[i]+=number[i-1];
        if(number[i]>=K){
            long long int now=i,count=number[i-1];
            long long int next,made=0;
            for(long long int j = 1; j <= 9; j++){
                if(K<=runrun[i][j]+count){
                    next=j;
                    made=j;
                    break;
                }
                count+=runrun[i][j];
            }
            now=i-1;
            //cout<<made<<" "<<next<<" "<<count<<endl;
            while(now!=-1){
                for(long long int j = max(next-1,0LL); j <= min(next+1,9LL); j++){
                    if(K<=runrun[now][j]+count){
                        next=j;
                        made=10*made+j;
                        break;
                    }
                    count+=runrun[now][j];               
                }
                now--;
            }
            cout<<made<<endl;
            return 0;
        }
    }
}


Measured memory_bytes: 256