#include <bits/stdc++.h> 

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

using u128 = unsigned __int128; 
using i128 = __int128; 

void solve() {
	std::string N; std::cin >> N;
	int n = (int)N.size();

	std::string ans = "";
	int a = -1;
	for(int i = 0; i < n; i ++) {
		int x = N[i] - '0';
		if(x > 5) {
			for(int j = i; j < n; j ++) ans += '5';
			break;
		} else if(x < 4) {
			if(a == -1) {
				ans = "";
				for(int j = 0; j < n - 1; j ++) ans += '5';
			} else {
				ans[a] = '4';
				for(int j = a + 1; j < i; j ++) ans[j] = '5';
				for(int j = i; j < n; j ++) ans += '5';
			}
			break;
		} else {
			ans += N[i];
			if(N[i] == '5') a = i;
		}
	}

	std::cout << ans;
} 

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

	int T = 1; 
	//std::cin >> T; 

	while (T--) { 
		solve(); 
	} 
	return 0; 
}