36     std::unordered_map<TKey, TEntry> map;  variable
51         for(iterator it = map.begin(); it != map.end(); ++it) {  in sort()
80         iterator it = map.find(key);  in add()
81         if (it == map.end()) {  in add()
82             it = map.insert(std::make_pair(key, TEntry(e))).first;  in add()
90         iterator it = map.find(key);  in add()
91         if (it == map.end()) {  in add()
92             it = map.insert(std::make_pair(key, TEntry(key))).first;  in add()
100         iterator it = map.find(key);  in subtract()
101         if ((it != map.end()) && it->second.subtract(e)) {  in subtract()
102             map.erase(it);  in subtract()
107         iterator it = map.find(key);  in drop()
108         if (it != map.end()) {  in drop()
113     inline iterator begin() { return map.begin(); }  in begin()
114     inline iterator end() { return map.end(); }  in end()