#include <bits/stdc++.h>
using namespace std;
int main() {
  int N;
  cin >> N;
  int r = N % 10;
  if (r == 3) {
    cout << "bon" << endl;
  } else if (r == 0 || r == 1 || r == 6 || r == 8) {
    cout << "pon" << endl;
  } else {
    cout << "bon" << endl;
  }
}
