initialization for STL priority queue

Question

I\'m still confused about priority queue in STL. Here is the objective I wanna achieve, say: I have a structure called Record, which contains a string word and a int counter. Fo

Answer 1

Your code does work, with two small changes:

• Uncomment the definition of Record::operator<(), since that's needed by the priority queue's default comparator.
• Change the declaration to bool operator<(const Record &) const (note the extra const), since the priority queue has to compare using references to const objects.

Alternatively, declare it as a free function, outside the class definition:

bool operator<(const Record &l, const Record &r) {return l.count > r.count;}

or define your own functor, and provide that as the appropriate template argument:

struct CompareRecords
{
    bool operator()(const Record &l, const Record &r) {return l.count > r.count;}
};

typedef priority_queue, CompareRecords> RecordQueue;