/* -*- c++ -*- */
/*
 * Copyright 2004,2012 Free Software Foundation, Inc.
 *
 * This file is part of GNU Radio
 *
 * GNU Radio is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3, or (at your option)
 * any later version.
 *
 * GNU Radio is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#include <gnuradio/trellis/quicksort_index.h>

namespace gr {
namespace trellis {

template <class T>
void SWAP(T& a, T& b)
{
    T temp = a;
    a = b;
    b = temp;
}

template <class T>
void quicksort_index(std::vector<T>& p, std::vector<int>& index, int left, int right)
{
    if (left < right) {
        int i = left;
        int j = right + 1;
        T pivot = p[left];
        do {
            do
                i++;
            while ((p[i] < pivot) && (i < right));
            do
                j--;
            while ((p[j] > pivot) && (j > left));
            if (i < j) {
                SWAP<T>(p[i], p[j]);
                SWAP<int>(index[i], index[j]);
            }
        } while (i < j);
        SWAP<T>(p[left], p[j]);
        SWAP<int>(index[left], index[j]);
        quicksort_index<T>(p, index, left, j - 1);
        quicksort_index<T>(p, index, j + 1, right);
    }
}

// instantiate an <int> version of the quicksort_index
// template <int> void SWAP (int & a, int & b);
template void
quicksort_index<int>(std::vector<int>& p, std::vector<int>& index, int left, int right);

} /* namespace trellis */
} /* namespace gr */
