#include <bits/stdc++.h>

using namespace std;

using ll = long long;

int main() {
    ios::sync_with_stdio(false); cout.tie(nullptr); cin.tie(nullptr);
    ll n; cin >> n;
    string s = to_string(n);
    ll one = 1;
    for (int i = 1; i < s.size(); ++i)
        s[i] = '0', one *= 10;
    ll number = stoll(s, nullptr, 10);
    if (n - number >= number + one - n)
        number += one;
    cout << number << '\n';
    return 0;
}