#include <bits/stdc++.h>

using namespace std;
void fast_io() {
    ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
}

int main() {
    fast_io();
    vector<string> s{""};
    string nupc = "NUPC";
    for (int i = 0; i < 4; i++) {
        vector<string> s_new;
        for (string t : s) {
            t += nupc[i];
            s_new.push_back(t);
            s_new.push_back(t + t);
        }
        swap(s, s_new);
    }
    sort(s.begin(), s.end());
    int k;
    cin >> k;
    cout << s[k - 1] << endl;
}