/**
* Add an element to the heap conditionally:
* (1) Add the element if we are not on full capacity.
* (2) If we are on full capacity, add the element only after comparison.
*/
bool add (const value_type& value) {
if (size<K) { heap.push(value); ++size; return true; }
else if (false==compare(heap.top(),value)) {
heap.pop ();
heap.push (value);
return true;
} else {
return false;
}
}
void pop () { if (0<size) { heap.pop(); --size; } }
