Sample code for Andreu's project. It should get the data inside the <text> tag of a simple xml file and separate it into words.

gistfile1.cpp

void readFile()
{
  ifstream file;
  char c;
  enum ReadState {
    StartFile, EndFile, Tag, Text
  }; 
  ReadState state = StartFile;
  ReadState lastState = StartFile;
  
  stringstream ss;
  
  while(file)
  {
    file >> c;
    switch(state)
    {
      case StartFile:
        if(c=='<')
        {
          ss.str("");
          state = Tag;
          lastState = StartFile;
        }
        break;
        
      case Tag:
        if(c=='>')
        {
          if(ss.str().INSENSITIVE_EQUAL("text")) // Implement INSENSITIVE_EQUAL
          {
            state = Text;
          }
          else
          {
            state = lastState;
          }
        }
        break;
        
      case Text:
        readText(file);
        state = EndFile;
        break;
    }
  }
}

void readText(istream file)
{
  stringstream ss;
  char c;
  bool hasAt = false;
  bool startsWithLT = false;
  
  while(file)
  {
    file >> c;
    
    if(ss.str().length() == 0)
    {
      startsWithLT = (c == '<');
    }
    
    if(c==' ' || c=='\n' || c=='\r' || c=='\t') // Add punctuation too?
    {
      if(startsWithLT && ss.str().INSENSITIVE_EQUAL("</text>"))
      {
        return;
      }
      
      if(hasAt)
      {
        // Check if it's an email
      }
      
      // Here we would save the word somewhere
      useWord(ss.str());
      
      hasAt = false;
      ss.str("");
    }
    else
    {
      hasAt = hasAt || (c == '@');
      
      ss << c;
    }
  }
}