quicksort.h

// Copyright (c) 2013 Craig Henderson
// https://github.com/cdmh/sorting_algorithms

#include "sort.h"
#include "quicksort.detail.h"

namespace cdmh {

// Quick Sort
//     Worst case performance       O(n2) (extremely rare)
//     Best case performance        O(n log n)
//     Average case performance     O(n log n)
//     Worst case space complexity  O(n) auxiliary (naive) O(log n) auxiliary (Sedgewick 1978)
// http://en.wikipedia.org/wiki/Quicksort

template<typename It, typename Pred=std::less<typename std::iterator_traits<It>::value_type>>
inline void quicksort(It begin, It end, Pred pred=Pred())
{
    if (std::distance(begin, end) > 1)
    {
        auto splits = detail::quicksort_splits(begin, end, pred);
        quicksort(begin, splits.first, pred);
        quicksort(splits.second, end, pred);
    }
}

}   // namespace cdmh

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