#include <bits/stdc++.h>
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <bitset>
#include <queue>
#include <stack>
#include <sstream>
#include <cstring>
#include <numeric>
#include <ctime>
#include <iomanip>

#define re return
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int) (x).size())
#define rep(i, n) for (int i = 0; i < (n); i++)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; i--)
#define sqr(x) ((x) * (x))
#define sqrt(x) sqrt(abs(x))
#define tr(x, y) ((x)*(x) + (y)*(y))

using namespace std;

typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
typedef vector <int> vi;
typedef vector <ll> vll;
typedef long double LD;

const LD pi = 3.141592653589793238462643;

string s;
int was[100];
int n;
int a[1000];

string get_ans(int x)
{
    string c = "10012233445566778899";
    re c.substr(0, x);
}

bool ch()
{
    rep(i, 10) if (was[i] > 2) re 0;
    re 1;
}

int main()
{
    #ifdef EKLER
        //freopen("input.txt", "r", stdin);
        //freopen("output.txt", "w", stdout);
    #else
        //freopen("input.txt", "r", stdin);
        //freopen("output.txt", "w", stdout);
    #endif

    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> s;
    n = sz(s);
    rep(i, sz(s))
    {
        a[i] = s[i] - '0';
    }
    string ans = "";
    string inf = "";
    rep(i, n) ans += "9";
    inf = ans;
    string tmp = "";
    int pos;
    string cur = "";
    rep(i, n)
    {
        int k = a[i] + 1;
        if (!ch()) break;
        while(k <= 9 && was[k] == 2) k++;
        if (k <= 9)
        {
            was[k]++;
            tmp = cur;
            cur += (char)(k + '0');
            pos = i + 1;
            for (int t = pos; t < n; t++)
            {
                rep(j, 10)
                {
                    if (was[j] < 2)
                    {
                        cur += (char)(j + '0');
                        was[j]++;
                        break;
                    }
                }
            }
            ans = min(ans, cur);
            rep(t, 10) was[t] = 0;
            rep(j, i) was[a[j]]++;
            cur = tmp;
        }
        cur += s[i];
        was[a[i]]++;
    }
    if (s == "99") {
        cout << 100;
        re 0;
    }
    if (s == "9") {
        cout << 10;
        re 0;
    }
    if (ans == inf && n > 2) ans = get_ans(n + 1);
    cout << ans;
    re 0;
}