#define _GLIBCXX_DEBUG
#define ll long long
#include <bits/stdc++.h>
using namespace std;

int main() {
  string S; cin >> S;
  int s = S.find("pain");
  if(s != -1){
    string T = S.substr(0, s);
    int ans = 0;
    for(int i = 0; i < (int)T.size()-2; i++){
      string U = "";
      U += T[i]; U += T[i+1]; U += T[i+2];
      if(U == "pon") ans++;
    }
    if(ans < 2) ans = 0;
    cout << ans-1 << endl;
  }else{
    cout << s << endl;
  }
}