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

#define int long long

int get(vector<int> cnt, int n) {
      int len = 0;
      for(int x : cnt) len += x;
      string s = to_string(n);
      if(len < s.length() || len > s.length()+1) return -1;
      string ans;
      if(len > s.length()) goto put_increasing;
      for(char c : s){
            int dig = c-'0';
            if(cnt[dig]) ans += c, cnt[dig]--;
            else {
                  for(int d = dig+1; d <= 9; d++) {
                        if(cnt[d]) {
                              ans += d + '0';
                              cnt[d]--;
                              goto put_increasing;
                        }
                  }
                  return -1;
            }
      }
      put_increasing:
      for(int dig = 1; dig <= 9; dig++) while(cnt[dig]--) ans += dig+'0';
      int res = stoll(ans);
      if(res == n) return -1;
      return res;
}

int solve(int n) {
      int ans = 99999999988888888;
      for(int mask = 0; mask < (1<<9); mask++) {
            vector<int> cnt(10);
            for(int dig = 1; dig <= 9; dig++) {
                  if(mask >> (dig-1) & 1) cnt[dig] = dig;
            }
            int best = get(cnt, n);
            if(best != -1) ans = min(ans, best);
      }
      return ans;
}

#undef int

int main() {
      int n; cin >> n ;
      cout << solve(n);
}