#include <algorithm>
#include <bitset>
#include <cmath>
#include <complex>
#include <cstring>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <regex>
#include <set>
#include <stack>
#include <string>
#include <vector>

const int MOD = 1e9 + 7;
const int iINF = 2147483647 / 2;
const long long int llINF = 9223372036854775807 / 2;

using namespace std;
using ll = long long int;
using vl = vector<ll>;
using vvl = vector<vector<ll>>;
using vvvl = vector<vector<vector<ll>>>;

typedef pair<ll, ll> pll;
bool paircomp(const pll &a, const pll &b) {
  if (a.first == b.first)
    return a.second < b.second;
  return a.first < b.first;
}

#define REP(i, n) for (ll i = 0; i < (n); i++)
#define RREP(i, n) for (ll i = (n)-1; i >= 0; i--)
#define FOR(i, a, b) for (ll i = (a); i < (b); i++)
#define AUTO(i, m) for (auto &i : m)
#define ALL(a) (a).begin(), (a).end()
#define MAX(vec) *std::max_element(vec.begin(), vec.end())
#define MIN(vec) *std::min_element(vec.begin(), vec.end())
#define ARGMAX(vec)                                                            \
  std::distance(vec.begin(), std::max_element(vec.begin(), vec.end()))
#define ARGMIN(vec)                                                            \
  std::distance(vec.begin(), std::min_element(vec.begin(), vec.end()))
#define REV(T) greater<T>()
#define PQ(T) priority_queue<T, vector<T>, greater<T>>
#define VVL(a, b, c) vector<vector<ll>>(a, vector<ll>(b, c))
#define VV(T, a, b, c) vector<vector<T>>(a, vector<T>(b, c))
#define VVVL(a, b, c, d)                                                       \
  vector<vector<vector<ll>>>(a, vector<vector<ll>>(b, vector<ll>(c, d)))
#define VVV(T, a, b, c, d)                                                     \
  vector<vector<vector<T>>>(a, vector<vector<T>>(b, vector<T>(c, d)))
#define SP(a) setprecision(a)
#define SQRT(a) sqrt((long double)(a))
#define DPOW(a, b) pow((long double)(a), (long double)(b))
#define UNIQUE(vec)                                                            \
  do {                                                                         \
    sort(ALL((vec)));                                                          \
    (vec).erase(std::unique(ALL((vec))), (vec).end());                         \
  } while (0)

ll POW(ll n, ll m) {
  if (m == 0) {
    return 1;
  } else if (m % 2 == 0) {
    ll tmp = POW(n, m / 2);
    return (tmp * tmp);
  } else {
    return (n * POW(n, m - 1));
  }
}

int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  ll K;
  ll sum = 0;
  cin >> K;
  if (K <= 9) {
    cout << K << endl;
    return 0;
  }
  PQ(ll) Q;
  REP(i, 9) Q.push(i + 1);
  ll ans = 0;
  REP(i, K) {
    ans = Q.top();
    Q.pop();
    ll po = ans % 10;
    if (ans % 10 != 0)
      Q.push(ans * 10 + po - 1);
    if (ans % 10 != 9)
      Q.push(ans * 10 + po + 1);
    Q.push(ans * 10 + po);
  }
  cout << ans << endl;
  /*if (K <= 9) {
    cout << K << endl;
    return 0;
  }
  FOR(i, 1, 10) A[i] = i + 1;
  vvl P = VVL(11, 10, 1);
  vvl DP = VVL(11, 10, 0);
  vvl B(10);
  REP(i, 9) B[0].push_back(i + 1);

  vl ANS(1e5 + 1);
  // vl P(i,10)
  REP(k, 10) {
    P[k + 1][0] = P[k][0] + P[k][1]+sum;
    FOR(i, 1, 9) { P[k + 1][i] = P[k][i - 1] + P[k][i] + P[k][i + 1]+sum; }
    P[k + 1][9] = P[k][8] + P[k][9]+sum;
  }*/

  /*REP(k, 10) {
    ll sum = 0;
    P[k + 1][0] = P[k][0] + P[k][1];
    FOR(i, 1, 9) { P[k + 1][i] = P[k][i - 1] + P[k][i] + P[k][i + 1]; }
    P[k + 1][9] = P[k][8] + P[k][9];
  }
  // REP(i, 10) cout << P[2][i] << endl;
  REP(i, 10) {
    FOR(j, 1, 10) { DP[i][j + 1] = DP[i][j] + P[i][j]; }
  }
  REP(i, 10) {
    cout << i << " ";
    FOR(j, 0, 10) {
      if (i > 0)
        DP[i][j + 1] += DP[i - 1][10];
      cout << DP[i][j + 1] << " ";
    }
    cout << endl;
  }
  ll yo = K;
  for (ll i = 9; i >= 0; i--) {
    ll po = upper_bound(ALL(DP[i]), yo) - DP[i].begin();
    // cout << DP[i][po - i] << endl;
    if (po > 1 && i > 0)
      yo -= DP[i][po - 1];
    cout << po - 1 << "," << yo << endl;
  }*/

  return 0;
}


Measured memory_bytes: 2420