#include <bits/stdc++.h>
using namespace std;

#ifdef _RUTHEN
#include <debug.hpp>
#else
#define show(...) true
#endif

using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); i++)
template <class T> using V = vector<T>;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    long long N;
    cin >> N;
    N--;
    V<pair<int, int>> A;
    for (int a = 1; a <= 9; a++) {
        for (int b = a + 1; b <= 9; b++) {
            A.push_back({a, b});
        }
    }
    long long d = N / A.size();
    auto [a, b] = A[N % 36];
    cout << a;
    rep(i, d) cout << b;
    cout << b << '\n';
    return 0;
}