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copied!<p>If possible, I'd suggest breaking the logic up into slightly smaller units, and pushing more of the logic into the classes -- right now, <code>main</code> does quite a lot more than I'd like to see there, and (particularly) knows more about the internals of the classes than I'd like to see either.</p> <p>If I were doing it, I'd start with a map that knew how to filter out words, so it can only accept what it's supposed to:</p> <pre><code>class Map { std::map<std::string, int> counts; public: struct Filter { virtual bool operator()(std::string const &) const = 0; }; Map(Filter const &f) : filter(f) {} bool InsertWord(std::string const &word) { return filter(word) && (++counts[word] != 0); } friend std::ostream &operator<<(std::ostream &os, Map const &m) { std::copy(m.counts.begin(), m.counts.end(), std::ostream_iterator<count>(std::cout, "\n")); return os; } private: Filter const &filter; }; </code></pre> <p>Then we'd need some derivatives of Filter to do the real filtering. These probably don't work the way you really want; they're really just placeholders:</p> <pre><code>struct Num : Map::Filter { bool operator()(std::string const &w) const { return isdigit(w[0]) != 0; } }; struct Punct : Map::Filter { bool operator()(std::string const &w) const { return ispunct(w[0]) != 0; } }; struct Letter : Map::Filter { bool operator()(std::string const &w) const { return isalpha(w[0]) != 0; } }; </code></pre> <p>Then MapWorks can delegate almost all the real work to the Map (which in turn uses a Filter):</p> <pre><code>class MapWorks { Map num; Map punct; Map letter; public: // For the moment, these allocations just leak. // As long as we only create one MapWorks object, // they're probably not worth fixing. MapWorks() : num(Map(*new Num())), punct(Map(*new Punct())), letter(Map(*new Letter())) {} // Try adding the word until we find a Map // that accepts it. bool push_back(std::string const &word) { return num.InsertWord(word) || punct.InsertWord(word) || letter.InsertWord(word); } // Write out by writing out the individual Map's: friend std::ostream &operator<<(std::ostream &os, MapWorks const &m) { return os << m.num << "\n" << m.punct << "\n" << m.letter << "\n"; } }; </code></pre> <p>With these in place, <code>main</code> becomes pretty simple: (though for the moment, I've just had it read a whole file instead of looking for "BEGIN" and "FINIS"):</p> <pre><code>int main() { MapWorks m; std::string temp; while (std::cin >> temp) m.push_back(temp); std::cout << m; return 0; } </code></pre> <p>There are a few other bits and pieces, such as typedef'ing the count type and defining an inserter for it, but they're pretty minor details.</p>

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