#include<bits/stdc++.h>
using namespace std;

#define ll long long
#define ull unsigned long long
#define ld  long double

using LL = long long; using ULL = unsigned long long;
using VI = vector<int>; using VVI = vector<VI>; using VVVI = vector<VVI>;
using VL = vector<LL>; using VVL = vector<VL>; using VVVL = vector<VVL>;
using VB = vector<bool>; using VVB = vector<VB>; using VVVB = vector<VVB>;
using VD = vector<double>; using VVD = vector<VD>; using VVVD = vector<VVD>;
using VC = vector<char>; using VS = vector<string>; using VVC = vector<VC>;
using PII = pair<int,int>; using PLL = pair<LL,LL>; using PDD = pair<double,double>; using PIL = pair<int,LL>;
using MII = map<int,int>; using MLL = map<LL,LL>;
using SI = set<int>; using SL = set<LL>;
using MSI = multiset<int>; using MSL = multiset<LL>;
template<class T> using MAXPQ = priority_queue<T>;
template<class T> using MINPQ = priority_queue< T, vector<T>, greater<T> >;

const ll MOD = 1000000007;
const ll MOD2 = 998244353;
const ll INF = 1LL << 60;
#define PI  3.14159265358979323846

#define FOR(i, a, b) for(int i = (a); i < (b); ++i)
#define REP(i, n) FOR(i, 0, n)
#define EACH(e, v) for(auto &e : v)
#define RITR(it, v) for(auto it = (v).rbegin(); it != (v).rend(); ++it)
#define ALL(v) v.begin(),v.end()

vector<ll> x8={1,1,1,0,0,-1,-1,-1},y8={1,0,-1,1,-1,1,0,-1};
int dx4[4]={1,-1,0,0}, dy4[4]={0,0,1,-1};

/*
memo
-uf,RMQ(segtree),BIT,BIT2,SegTree,SegTreeLazy
-isprime,Eratosthenes,gcdlcm,factorize,divisors,modpow,moddiv
nCr(+modnCr,inverse,extend_euclid.powmod),tobaseB,tobase10
-dijkstra,Floyd,bellmanford,sccd,topological,treediamiter
-compress1,compress2,rotate90

-co,ci,fo1,fo2,fo3,fo4
-bitsearch,binaryserach
-bfs
-SegTreedec,SegTreeLazydec
*/

/*
5333333 : 4444444
4333333 :  555555
4533333 : 4444444
*/

int main(){
    cin.tie(0);
    ios_base::sync_with_stdio(0);
    string N; cin >> N;
    ll K = N.size();
    string ans = "";
    if(N[0] < '4'){
        for(ll i = 0; i < K-1; i++) ans += '5';
    }
    else{
        VL div(K);
        for(ll i = 0; i < K; i++){
            if(N[i] < '4') div[i] = 0;
            else if(N[i] == '4') div[i] = 1;
            else if(N[i] == '5') div[i] = 2;
            else div[i] = 3;
        }

        ll m0 = K;
        for(ll i = K-1; i >= 0; i--){
            if(div[i] == 0) m0 = i;
        }

        ll r1=-1,r2=-1,r3=-1;
        for(ll i = 0; i < m0; i++){
            if(div[i]==1) r1 = i;
            if(div[i]==2) r2 = i;
            if(div[i]==3) r3 = i;
        }

        ll rm = max(r2,r3);
        if(rm == -1 and m0 < K){
            for(ll i = 0; i < K-1; i++) ans += '5';
        }   
        else if(rm == -1 and m0 == K){
            ll f = 0;
            for(ll i = 0; i < m0; i++){
                if(div[i]==1) ans += (f? '5':'4');
                if(div[i]==2) ans += '5';
                if(div[i]==3){
                    ans += '5';
                    f = 1;
                }
            }
        }
        else{
            ll f = 0;
            for(ll i = 0; i < m0; i++){
                if(div[i]==1) ans += (f? '5':'4');
                if(div[i]==2) ans += '5';
                if(div[i]==3){
                    ans += '5';
                    f = 1;
                }
            }

            if(!f and m0 < K){
                ans[r2] = '4';
            }

            for(ll i = 0; i < K-m0; i++){
                ans += '5';
            }
        }
        //cout << m0 << " " << r2 << '\n';
    }
    
    //assert(ans <= N);
    cout << ans << '\n';
}