#include <bits/stdc++.h>

using i64 = long long;
using u64 = unsigned long long;
using u32 = unsigned;

using u128 = unsigned __int128;
using i128 = __int128;

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);

    std::string s;
    std::cin >> s;
    int N = s.size();

    for (int i = 0; i < N; i++) {
        if (s[i] > '5') {
            for (int j = i; j < N; j++) s[j] = '5';
        } else if (s[i] < '4') {
            int j = i - 1;
            while (j >= 0 && s[j] != '5') j--;
            if (j == -1) {
                std::cout << std::string(N - 1, '5');
                return 0;
            } else {
                s[j] = '4';
                for (int k = j + 1; k < N; k++) s[k] = '5';
            }
        }
    }
    std::cout << s << '\n';

    return 0;
}