#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <atcoder/modint>
using namespace std;
using i32 = int;
using u32 = unsigned int;
using i64 = long long;
using u64 = unsigned long long;
#define rep(i,n) for(int i=0; i<(int)(n); i++)
const i64 INF = 1001001001001001001;

using Modint = atcoder::static_modint<998244353>;


int main(){
    int N; cin >> N; N--;
    int c = N / 36;
    vector<pair<int,int>> ab;
    rep(b,9) rep(a,b) ab.push_back({a+1,b+1});
    sort(ab.begin(), ab.end());
    cout << ab[N%36].first << string(c+1,'0'+ab[N%36].second) << '\n';
    return 0;
}



struct ios_do_not_sync{
    ios_do_not_sync(){
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
    }
} ios_do_not_sync_instance;