push_heap

template<class RanIt>
    void push_heap(RanIt first, RanIt last);
template<class RanIt, class Pred>
    void push_heap(RanIt first, RanIt last, Pred pr);

The first template function reorders the sequence designated by iterators in the range [first, last) to form a new heap ordered by operator<. Iterators in the range [first, last - 1) must designate an existing heap, also ordered by operator<. Thus, first != last must be true and *(last - 1) is the element to add to (push on) the heap.

The function evaluates the ordering predicate X < Y ceil(log(last - first)) times, at most.

The second template function behaves the same, except that it replaces operator<(X, Y) with pr(X, Y).

Sample programs: heap and heap (predicate version).