#include <bits/stdc++.h>
#define endl '\n'
using namespace std;
typedef pair<int, int> PII;
using ll = long long;
using ULL = unsigned long long;
const int N = 1e7 + 5;

ll res;
int m = 16;
string ans = "";
inline void solve() {
    cin >> res;
    if (res == 0) {
        cout << "0" << endl;
        return;
    }
    while (res) {
        auto x = res%m;
        if (x >= 10 && x <= 17) ans += 'A'+x-10;
        else ans += x + '0';
        res /= m;
    }
    reverse(ans.begin(),ans.end());
    cout << ans << endl;
}

int main() {
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int _ = 1;
    //int _; cin >> _;
    while (_--) solve();
    return 0;
}