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

int main() {
    int K;
    cin >> K;

    const int size = 4;
    vector<string> decompressed;
    string nupc = "NUPC";
    for (int bit = 0; bit < (1 << size); bit++) {
        string tmp = "";
        for (int i = 0; i < size; i++) {
            tmp.push_back(nupc[i]);
            if (bit & (1 << i)) {
                tmp += tmp;
            }
        }
        decompressed.push_back(tmp);
    }

    sort(decompressed.begin(), decompressed.end());

    cout << decompressed[K - 1] << endl;
}