#include <bits/stdc++.h>
using namespace std;
int main() {
  int N;
  cin >> N;
  N = N % 10;
  if (N == 2 && 4 && 5 && 7 && 9) {
    cout << N << endl;
  } else if (N == 0 && 1 && 6 && 8) {
    cout << "pon" << endl;
  } else if (N == 3) {
    cout << "bon" << endl;
  }
}
