#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  string ans;
  switch (n % 10) {
    case 3:
      cout << "bon\n";
      break;
    case 0:
    case 1:
    case 6:
    case 8:
      cout << "pon\n";
      break;
    default:
      cout << "bon\n";
      break;
  }
}
