#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();

    if (s[0] <= '4') {
        std::cout << std::string(N - 1, '5');
    } else if (s[0] > '5') {
        std::cout << std::string(N, '5');
    }

    return 0;
}