#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
  #include "settings/debug.cpp"
  #define _GLIBCXX_DEBUG
#else
  #define Debug(...) void(0)
#endif
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using ull = unsigned long long;

int main() {
  while (true) {
    int x;
    cin >> x;
    if (x == 0) break;
    cout << "yukicoder"[x - 1] << endl;
  }
  return 0;
}