C++ (226)

I know I'm kinda late for the party, but this seemed like a fun problem and lack of entries using C-family languages bothered me.

So here's a C++ function using no regexp or string substitution, just some simple math:

void f(){char c;int o=0,i,j;while(cin>>c){c=='p'||c==80?cin.ignore(9,58):cin.unget();cin>>i>>c&&c==45?cin>>j>>c&&(c=='e'||c=='o')?cin.ignore(9,44),c=='e'?i+=i&1,j+=!(j&1):(i+=!(i&1),j+=j&1),o+=(j-i)/2:(o+=j-i):0;++o;}cout<<o;}

Ungolfed:

void f()
{
  char c;
  int o=0,i,j;
  while(cin>>c)
  {
    c=='p'||c==80?cin.ignore(9,58):cin.unget();
    cin>>i>>c&&c==45?
      cin>>j>>c&&(c=='e'||c=='o')?
        cin.ignore(9,44),
        c=='e'?
          i+=i&1,j+=!(j&1)
        :(i+=!(i&1),j+=j&1),o+=(j-i)/2
      :(o+=j-i)
    :0;
    ++o;
  }
  cout<<o;
}

I didn't say it would be readable, now did I? :) Ternary operators are hell. I tried my best to (sort of) format it, though, so I hope it helps at least a little bit.

Usage:

#include <iostream>
using namespace std;

void f(){char c;int o=0,i,j;while(cin>>c){c=='p'||c==80?cin.ignore(9,58):cin.unget();cin>>i>>c&&c==45?cin>>j>>c&&(c=='e'||c=='o')?cin.ignore(9,44),c=='e'?i+=i&1,j+=!(j&1):(i+=!(i&1),j+=j&1),o+=(j-i)/2:(o+=j-i):0;++o;}cout<<o;}

int main()
{
  f();
}