#include <iostream>
#include <cmath>
#include <iomanip>
#include <string>
#include <vector>
#include <algorithm>
#include <set>
#include <map>

using namespace std;

int main() {
    std::cin.tie(NULL);
    std::cout.tie(NULL);

    long long int n;
    std::cin >> n;
    n++;
    std::string s = std::to_string(n);
    for (int i = 1; i < s.size(); ++i) {
        if (s[i] != s[i - 1])
            continue;
        if (s[i] != '9') {
            s[i]++;
            for (int j = i + 1; j < s.size(); j += 2) {
                s[j] = '0';
                if (j + 1 < s.size())
                    s[j + 1] = '1';
            }
        }
        else {
            if (i == 1) {
                s[1] = '1';
                s[0] = '0';
                s = "1" + s;
                for (int j = 3; j < s.size(); j += 2) {
                    s[j] = '0';
                    if (j + 1 < s.size())
                        s[j + 1] = '1';
                }
            }
            else {
                int j = i;
                while (true) {
                    s[j - 2]++;
                    s[j - 1] = '0';
                    s[j] = '1';
                    if (j - 3 >= 0 && s[j - 2] == s[j - 3]) {
                        if (s[j - 2] != '9') {
                            s[j - 2]++;
                            break;
                        }
                        if (j == 3) {
                            s[0] = '0';
                            s[1] = '1';
                            s = "1" + s;
                            ++i;
                            break;
                        }
                        j -= 2;
                    }
                    else
                        break;
                }
                for (j = i + 1; j < s.size(); j += 2) {
                    s[j] = '0';
                    if (j + 1 < s.size())
                        s[j + 1] = '1';
                }
            }
        }
        break;
    }
    std::cout << s;
}