#include <bits/stdc++.h>
using namespace std;
long long modpow(long long b, long long e, long long mod) {
  long long ans = 1;
  for (; e; b = b * b % mod, e /= 2)
    if (e & 1) ans = ans * b % mod;
  return ans;
}
int32_t main() {
  int n;
  cin >> n;
  if (n % 10 == 3) {
    cout << "bon" << endl;
  } else if (n % 10 == 0 || n % 10 == 1 || n % 10 == 6 || n % 10 == 8) {
    cout << "pon" << endl;
  } else
    cout << "bon" << endl;
}
