/**
* Removes the item with maximum priority from the queue, and
* returns it with its priority.
*/
std::pair<T, Priority> pop() {
assert(!empty());
heap_element top = heap[1];
swap(1, size());
heap.pop_back();
heapify(1);
index_map.erase(top.first);
return top;
}
//! Remove an item from the queue
bool remove(T item) {
// Ensure that the element is in the queue
typename index_map_type::iterator iter = index_map.find(item);
// only if the element is present in the first place do we need
// remove it
if(iter != index_map.end()) {
size_t i = iter->second;
swap(i, size());
heap.pop_back();
heapify(i);
// erase the element from the index map
index_map.erase(iter);
return true;
}
return false;
}
