STL源码剖析之算法：push_heap

template <class RandomAccessIterator>
inline void push_heap(RandomAccessIterator first, RandomAccessIterator last) {
    __push_heap_aux(first, last, distance_type(first), value_type(first));
}

template <class RandomAccessIterator, class Distance, class T>
inline void __push_heap_aux(RandomAccessIterator first,
                           RandomAccessIterator last, Distance*, T*) {
    __push_heap(first, Distance((last - first) - 1, Distance(0), T(*(last - 1)));
}

 

template <class RandomAccessIterator, class Distance, class T>
void __push_heap(RandomAccessIterator first, Distance holeIndex,
                 Distance topIndex, T value) {
    Distance parent = (holeIndex - 1)/2;
    while(holeIndex > topIndex && *(first + parent) < value) {
        *(first + holeIndex) = *(first + parent);
        holeIndex = parent;
        parent = (holeIndex - 1)/2;
    }
    *(first + holeIndex) = value;
}