Untitled

#include <bits/stdc++.h>
#define endl '\n'
#define maxn 105
#define TASK bai1
#define For(i,a,b) for ( int i = a; i <= b; i++ )
#define Ford(i,a,b) for ( int i = a; i >= b; i-- )
#define MOD 100000000000007

using namespace std;
string s ="";
int n;
void inp()
{
    cin >> n;
}
void solve()
{
    For(i,1,n)
    if(s.find(to_string(i)) > s.size()) s += to_string(i);
    cout << s;
}
int main()
{
    ios_base:: sync_with_stdio(0);
    cin.tie(0);
    if(fopen("bai1.inp","r")){
        freopen("bai1.inp","r",stdin);
    }
    inp();
    solve();
}