Inter.Net 55-1/Inter.Net 55-1.iso/CBuilder/Setup/BCB/data.z/algorith.cc

C/C++ Source or Header | 1998-02-09 | 80.0 KB | 2,535 lines

#ifndef __ALGORITH_CC
#define __ALGORITH_CC
#pragma option push -b -a4 -Vx- -Ve- -w-inl -w-aus -w-sig

/***************************************************************************
 *
 * algorithm.cc - Non-inline definitions for the Standard Library algorithms
 *
 * $Id: algorithm.cc,v 1.4 1996/08/30 00:35:17 smithey Exp $
 *
 ***************************************************************************
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Hewlett-Packard Company makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 *
 ***************************************************************************
 *
 * (c) Copyright 1994, 1995 Rogue Wave Software, Inc.
 * ALL RIGHTS RESERVED *
 * The software and information contained herein are proprietary to, and
 * comprise valuable trade secrets of, Rogue Wave Software, Inc., which
 * intends to preserve as trade secrets such software and information.
 * This software is furnished pursuant to a written license agreement and
 * may be used, copied, transmitted, and stored only in accordance with
 * the terms of such license and with the inclusion of the above copyright
 * notice.  This software and information or any other copies thereof may
 * not be provided or otherwise made available to any other person.
 *
 * Notwithstanding any other lease or license that may pertain to, or
 * accompany the delivery of, this computer software and information, the
 * rights of the Government regarding its use, reproduction and disclosure
 * are as set forth in Section 52.227-19 of the FARS Computer
 * Software-Restricted Rights clause.
 *
 * Use, duplication, or disclosure by the Government is subject to
 * restrictions as set forth in subparagraph (c)(1)(ii) of the Rights in
 * Technical Data and Computer Software clause at DFARS 252.227-7013.
 * Contractor/Manufacturer is Rogue Wave Software, Inc.,
 * P.O. Box 2328, Corvallis, Oregon 97339.
 *
 * This computer software and information is distributed with "restricted
 * rights."  Use, duplication or disclosure is subject to restrictions as
 * set forth in NASA FAR SUP 18-52.227-79 (April 1985) "Commercial
 * Computer Software-Restricted Rights (April 1985)."  If the Clause at
 * 18-52.227-74 "Rights in Data General" is specified in the contract,
 * then the "Alternate III" clause applies.
 *
 **************************************************************************/

#include <stdcomp.h>

#ifndef _RWSTD_NO_NAMESPACE
namespace std {
#endif

//
// Forward declare raw_storage_iterator
//
template <class OutputIterator, class T>
class raw_storage_iterator;

//
// Non-modifying sequence operations.
//

template <class InputIterator, class Function>
Function for_each (InputIterator first, InputIterator last, Function f)
{
    while (first != last) f(*first++);
    return f;
}

template <class InputIterator, class T>
InputIterator find (InputIterator first, InputIterator last, const T& value)
{
    while (first != last && *first != value)
        ++first;
    return first;
}

template <class InputIterator, class Predicate>
InputIterator find_if (InputIterator first, InputIterator last, Predicate pred)
{
    while (first != last && !pred(*first)) ++first;
    return first;
}


template <class ForwardIterator1, class ForwardIterator2,
          class Distance>
ForwardIterator1 __find_end (ForwardIterator1 first1,
                                  ForwardIterator1 last1,
                                  ForwardIterator2 first2,
                                  ForwardIterator2 last2,
                                  Distance*)
{
   Distance d, d2;
   __initialize(d,Distance(0));
   __initialize(d2,Distance(0));
   distance(first2,last2,d);
   if (!d)
     return first1;
   distance(first1,last1,d2);
   ForwardIterator1 save = last1;

   while (d2 >= d)
   {
     if (equal(first2,last2,first1))
       save  = first1;
     __initialize(d2,Distance(0));
     distance(++first1,last1,d2);
   }
   return save;
}


template <class ForwardIterator1, class ForwardIterator2>
ForwardIterator1 find_end (ForwardIterator1 first1,
                                  ForwardIterator1 last1,
                                  ForwardIterator2 first2,
                                  ForwardIterator2 last2)
{
   return __find_end(first1,last1,first2,last2,
                     distance_type(first1));
}

template <class ForwardIterator1, class ForwardIterator2,
          class BinaryPredicate, class Distance>
ForwardIterator1 __find_end (ForwardIterator1 first1,
                                  ForwardIterator1 last1,
                                  ForwardIterator2 first2,
                                  ForwardIterator2 last2,
                                  BinaryPredicate pred,
                                  Distance*)
{
   Distance d, d2;
   __initialize(d,Distance(0));
   __initialize(d2,Distance(0));
   distance(first2,last2,d);
   if (!d)
     return first1;
   distance(first1,last1,d2);
   ForwardIterator1 save = last1;

   while (d2 >= d)
   {
     if (equal(first2,last2,first1,pred))
       save  = first1;
     __initialize(d2,Distance(0));
     distance(++first1,last1,d2);
   }
   return save;
}

template <class ForwardIterator1, class ForwardIterator2,
          class BinaryPredicate>
ForwardIterator1 find_end (ForwardIterator1 first1,
                                  ForwardIterator1 last1,
                                  ForwardIterator2 first2,
                                  ForwardIterator2 last2,
                                  BinaryPredicate pred)
{
   return __find_end(first1,last1,first2,last2,
                     pred,distance_type(first1));
}


template <class ForwardIterator1, class ForwardIterator2>
ForwardIterator1 find_first_of (ForwardIterator1 first1, ForwardIterator1 last1,
                                ForwardIterator2 first2, ForwardIterator2 last2)
{
    if (first2 == last2)
        return first1;
    ForwardIterator1 next = first1;
    while (next != last1)
    {
        if (find(first2,last2,*next) != last2)
            return next;
        next++;
    }
    return last1;
}

template <class ForwardIterator1, class ForwardIterator2,
          class BinaryPredicate>
ForwardIterator1 find_first_of (ForwardIterator1 first1,ForwardIterator1 last1,
                                ForwardIterator2 first2,ForwardIterator2 last2,
                                BinaryPredicate pred)
{
    if (first2 == last2)
        return first1;
    ForwardIterator1 next = first1;
    while (next != last1)
    {
        if (find_if(first2,last2,bind2nd(pred,*next)) != last2)
            return next;
        next++;
    }
    return last1;
}


template <class ForwardIterator>
ForwardIterator adjacent_find (ForwardIterator first, ForwardIterator last)
{
    if (first == last) return last;
    ForwardIterator next = first;
    while (++next != last)
    {
        if (*first == *next) return first;
        first = next;
    }
    return last;
}

template <class ForwardIterator, class BinaryPredicate>
ForwardIterator adjacent_find (ForwardIterator first, ForwardIterator last,
                             BinaryPredicate binary_pred)
{
    if (first == last) return last;
    ForwardIterator next = first;
    while (++next != last)
    {
        if (binary_pred(*first, *next)) return first;
        first = next;
    }
    return last;
}

#ifndef _RWSTD_NO_CLASS_PARTIAL_SPEC
template <class InputIterator, class T>
iterator_traits<InputIterator>::distance_type
count (InputIterator first, InputIterator last, const T& value)
{
    iterator_traits<InputIterator>::distance_type n = 0;
    while (first != last)
        if (*first++ == value) ++n;
}

template <class InputIterator, class Predicate>
iterator_traits<InputIterator>::distance_type
count_if (InputIterator first, InputIterator last, Predicate pred)
{
    iterator_traits<InputIterator>::distance_type n = 0;
    while (first != last)
    if (pred(*first++)) ++n;
}
#endif /* _RWSTD_NO_CLASS_PARTIAL_SPEC */

#ifndef _RWSTD_NO_OLD_COUNT
template <class InputIterator, class T, class Size>
void count (InputIterator first, InputIterator last, const T& value, Size& n)
{
    while (first != last)
        if (*first++ == value) ++n;
}

template <class InputIterator, class Predicate, class Size>
void count_if (InputIterator first, InputIterator last, Predicate pred,
               Size& n)
{
    while (first != last)
    if (pred(*first++)) ++n;
}
#endif /* _RWSTD_NO_OLD_COUNT */

template <class InputIterator1, class InputIterator2>
pair<InputIterator1, InputIterator2> mismatch(InputIterator1 first1,
                                              InputIterator1 last1,
                                              InputIterator2 first2)
{
    while (first1 != last1 && *first1 == *first2)
    {
        ++first1;
        ++first2;
    }
    pair<InputIterator1, InputIterator2> tmp(first1, first2);
    return tmp;
}

template <class InputIterator1, class InputIterator2, class BinaryPredicate>
pair<InputIterator1, InputIterator2> mismatch (InputIterator1 first1,
                                               InputIterator1 last1,
                                               InputIterator2 first2,
                                               BinaryPredicate binary_pred)
{
    while (first1 != last1 && binary_pred(*first1, *first2))
    {
        ++first1;
        ++first2;
    }
    pair<InputIterator1, InputIterator2> tmp(first1, first2);
    return tmp;
}

template <class ForwardIterator1, class ForwardIterator2,
      class Distance1, class Distance2>
ForwardIterator1 __search (ForwardIterator1 first1, ForwardIterator1 last1,
                           ForwardIterator2 first2, ForwardIterator2 last2,
                           Distance1*, Distance2*)
{
    Distance1 d1;
    __initialize(d1, Distance1(0));
    distance(first1, last1, d1);
    Distance2 d2;
    __initialize(d2, Distance2(0));
    distance(first2, last2, d2);

    if (d1 < d2) return last1;

    ForwardIterator1 current1 = first1;
    ForwardIterator2 current2 = first2;

    while (current2 != last2)
    {
        if (*current1++ != *current2++)
            if (d1-- == d2)
                return last1;
            else
            {
                current1 = ++first1;
                current2 = first2;
            }
    }
    return (current2 == last2) ? first1 : last1;
}

template <class ForwardIterator1, class ForwardIterator2,
          class BinaryPredicate, class Distance1, class Distance2>
ForwardIterator1 __search (ForwardIterator1 first1, ForwardIterator1 last1,
                           ForwardIterator2 first2, ForwardIterator2 last2,
                           BinaryPredicate binary_pred, Distance1*, Distance2*)
{
    Distance1 d1;
    __initialize(d1, Distance1(0));
    distance(first1, last1, d1);
    Distance2 d2;
    __initialize(d2, Distance2(0));
    distance(first2, last2, d2);

    if (d1 < d2) return last1;

    ForwardIterator1 current1 = first1;
    ForwardIterator2 current2 = first2;

    while (current2 != last2)
    {
        if (!binary_pred(*current1++, *current2++))
            if (d1-- == d2)
                return last1;
            else
            {
                current1 = ++first1;
                current2 = first2;
            }
    }
    return (current2 == last2) ? first1 : last1;
}

template <class ForwardIterator, class Distance, class Size, class T>
ForwardIterator __search_n (ForwardIterator first, ForwardIterator last,
                            Distance*, Size count, const T& value)
{
    Distance d;
    __initialize(d, Distance(0));
    distance(first, last, d);

    if (d < count || count <= 0) return last;

    Distance        span    = d - count;
    Size            matches = 0;
    ForwardIterator current = first;

    while (current != last)
    {
        if (*current++ != value)
        {
            if (span < matches + 1)
              return last;
            span   -= matches + 1;
            matches = 0;
            first   = current;
        }
        else
            if (++matches == count)
                return first;
    }

    return last;
}

template <class ForwardIterator, class Distance, class Size, class T,
          class BinaryPredicate>
ForwardIterator __search_n (ForwardIterator first, ForwardIterator last,
                            Distance*, Size count, const T& value,
                            BinaryPredicate pred)
{
    Distance d;
    __initialize(d, Distance(0));
    distance(first, last, d);

    if (d < count || count <= 0) return last;

    Distance        span    = d - count;
    Size            matches = 0;
    ForwardIterator current = first;

    while (current != last)
    {
        if (!pred(*current++, value))
        {
            if (span < matches + 1)
              return last;
            span   -= matches + 1;
            matches = 0;
            first   = current;
        }
        else
            if (++matches == count)
                return first;
    }

    return last;
}

//
// Modifying sequence operations.
//

template <class InputIterator, class OutputIterator>
OutputIterator copy (InputIterator first, InputIterator last,
                     OutputIterator result)
{
    while (first != last) *result++ = *first++;
    return result;
}

template <class BidirectionalIterator1, class BidirectionalIterator2>
BidirectionalIterator2 copy_backward (BidirectionalIterator1 first,
                                      BidirectionalIterator1 last,
                                      BidirectionalIterator2 result)
{
    while (first != last) *--result = *--last;
    return result;
}

template <class ForwardIterator1, class ForwardIterator2>
ForwardIterator2 swap_ranges (ForwardIterator1 first1, ForwardIterator1 last1,
                              ForwardIterator2 first2)
{
    while (first1 != last1) iter_swap(first1++, first2++);
    return first2;
}

template <class InputIterator, class OutputIterator, class UnaryOperation>
OutputIterator transform (InputIterator first, InputIterator last,
                          OutputIterator result, UnaryOperation op)
{
    while (first != last) *result++ = op(*first++);
    return result;
}

template <class InputIterator1, class InputIterator2, class OutputIterator,
      class BinaryOperation>
OutputIterator transform (InputIterator1 first1, InputIterator1 last1,
                          InputIterator2 first2, OutputIterator result,
                          BinaryOperation binary_op)
{
    while (first1 != last1) *result++ = binary_op(*first1++, *first2++);
    return result;
}

template <class ForwardIterator, class T>
void replace (ForwardIterator first, ForwardIterator last, const T& old_value,
              const T& new_value)
{
    while (first != last)
    {
        if (*first == old_value) *first = new_value;
        ++first;
    }
}

template <class ForwardIterator, class Predicate, class T>
void replace_if (ForwardIterator first, ForwardIterator last, Predicate pred,
                 const T& new_value)
{
    while (first != last)
    {
        if (pred(*first)) *first = new_value;
        ++first;
    }
}

template <class InputIterator, class OutputIterator, class T>
OutputIterator replace_copy (InputIterator first, InputIterator last,
                             OutputIterator result, const T& old_value,
                             const T& new_value)
{
    while (first != last)
    {
        *result++ = *first == old_value ? new_value : *first;
        ++first;
    }
    return result;
}

template <class Iterator, class OutputIterator, class Predicate, class T>
OutputIterator replace_copy_if (Iterator first, Iterator last,
                                OutputIterator result, Predicate pred,
                                const T& new_value)
{
    while (first != last)
    {
        if(pred(*first))
           *result++ = new_value;
        else
           *result++ = *first;
        ++first;
    }
    return result;
}

template <class ForwardIterator, class T>
#ifdef _RWSTD_FILL_NAME_CLASH
void std_fill (ForwardIterator first, ForwardIterator last, const T& value)
#else
void fill (ForwardIterator first, ForwardIterator last, const T& value)
#endif
{
    while (first != last) *first++ = value;
}

template <class OutputIterator, class Size, class T>
void fill_n (OutputIterator first, Size n, const T& value)
{
    while (n-- > 0) *first++ = value;
}

template <class ForwardIterator, class Generator>
void generate (ForwardIterator first, ForwardIterator last, Generator gen)
{
    while (first != last) *first++ = gen();
}

template <class OutputIterator, class Size, class Generator>
void generate_n (OutputIterator first, Size n, Generator gen)
{
    while (n-- > 0) *first++ = gen();
}

template <class InputIterator, class OutputIterator, class T>
OutputIterator remove_copy (InputIterator first, InputIterator last,
                            OutputIterator result, const T& value)
{
    while (first != last)
    {
        if (*first != value) *result++ = *first;
        ++first;
    }
    return result;
}

template <class InputIterator, class OutputIterator, class Predicate>
OutputIterator remove_copy_if (InputIterator first, InputIterator last,
                               OutputIterator result, Predicate pred)
{
    while (first != last)
    {
        if (!pred(*first)) *result++ = *first;
        ++first;
    }
    return result;
}

template <class InputIterator, class ForwardIterator>
ForwardIterator __unique_copy (InputIterator first, InputIterator last,
                               ForwardIterator result, forward_iterator_tag)
{
    *result = *first;
    while (++first != last)
        if (*result != *first) *++result = *first;
    return ++result;
}

template <class InputIterator, class OutputIterator, class T>
OutputIterator __unique_copy (InputIterator first, InputIterator last,
                              OutputIterator result, T*)
{
    T value = *first;
    *result = value;
    while (++first != last)
    {
        if (value != *first)
        {
            value = *first;
            *++result = value;
        }
    }
    return ++result;
}

template <class InputIterator, class ForwardIterator, class BinaryPredicate>
ForwardIterator __unique_copy (InputIterator first, InputIterator last,
                               ForwardIterator result,
                               BinaryPredicate binary_pred,
                               forward_iterator_tag)
{
    *result = *first;
    while (++first != last)
        if (!binary_pred(*result, *first)) *++result = *first;
    return ++result;
}

template <class InputIterator, class OutputIterator, class BinaryPredicate,
          class T>
OutputIterator __unique_copy (InputIterator first, InputIterator last,
                              OutputIterator result,
                              BinaryPredicate binary_pred, T*)
{
    T value = *first;
    *result = value;
    while (++first != last)
    {
        if (!binary_pred(value, *first))
        {
            value = *first;
            *++result = value;
        }
    }
    return ++result;
}

template <class BidirectionalIterator>
void __reverse (BidirectionalIterator first, BidirectionalIterator last,
                bidirectional_iterator_tag)
{
    while (true)
        if (first == last || first == --last)
            return;
        else
            iter_swap(first++, last);
}

template <class RandomAccessIterator>
void __reverse (RandomAccessIterator first, RandomAccessIterator last,
                random_access_iterator_tag)
{
    while (first < last) iter_swap(first++, --last);
}

template <class BidirectionalIterator, class OutputIterator>
OutputIterator reverse_copy (BidirectionalIterator first,
                             BidirectionalIterator last,
                             OutputIterator result)
{
    while (first != last) *result++ = *--last;
    return result;
}

template <class ForwardIterator, class Distance>
void __rotate (ForwardIterator first, ForwardIterator middle,
               ForwardIterator last, Distance*, forward_iterator_tag)
{
    for (ForwardIterator i = middle; ;)
    {
        iter_swap(first++, i++);
        if (first == middle)
        {
            if (i == last) return;
                middle = i;
        }
        else if (i == last)
            i = middle;
    }
}

template <class EuclideanRingElement>
EuclideanRingElement __gcd (EuclideanRingElement m, EuclideanRingElement n)
{
    while (n != 0)
    {
        EuclideanRingElement t = m % n;
        m = n;
        n = t;
    }
    return m;
}

template <class RandomAccessIterator, class Distance, class T>
void __rotate_cycle (RandomAccessIterator first, RandomAccessIterator last,
                     RandomAccessIterator initial, Distance shift, T*)
{
    T value = *initial;
    RandomAccessIterator ptr1 = initial;
    RandomAccessIterator ptr2 = ptr1 + shift;
    while (ptr2 != initial)
    {
        *ptr1 = *ptr2;
        ptr1 = ptr2;
        if (last - ptr2 > shift)
            ptr2 += shift;
        else
            ptr2 = first + (shift - (last - ptr2));
    }
    *ptr1 = value;
}

template <class RandomAccessIterator, class Distance>
void __rotate (RandomAccessIterator first, RandomAccessIterator middle,
               RandomAccessIterator last, Distance*,
               random_access_iterator_tag)
{
    Distance n = __gcd(last - first, middle - first);
    while (n--)
        __rotate_cycle(first, last, first + n, middle - first,
                       _RWSTD_VALUE_TYPE(first));
}


#ifndef _RWSTD_NO_NAMESPACE
}
namespace __rwstd {
#endif
extern unsigned _RWSTDExport long __long_random (unsigned long);
#ifndef _RWSTD_NO_NAMESPACE
}
namespace std {
#endif

template <class RandomAccessIterator, class Distance>
void __random_shuffle (RandomAccessIterator first, RandomAccessIterator last,
                       Distance*)
{
    if (!(first == last))
        for (RandomAccessIterator i = first + 1; i != last; ++i)
            iter_swap(i, first + Distance(__RWSTD::__long_random((i - first) + 1)));
}

template <class RandomAccessIterator, class RandomNumberGenerator>
void random_shuffle (RandomAccessIterator first, RandomAccessIterator last,
                     RandomNumberGenerator& rand)
{
    if (!(first == last))
        for (RandomAccessIterator i = first + 1; i != last; ++i)
            iter_swap(i, first + rand((i - first) + 1));
}

template <class BidirectionalIterator, class Predicate>
BidirectionalIterator partition (BidirectionalIterator first,
                                 BidirectionalIterator last, Predicate pred)
{
    while (true)
    {
        while (true)
        {
            if (first == last)
                return first;
            else if (pred(*first))
                ++first;
            else
                break;
        }
        --last;
        while (true)
        {
            if (first == last)
                return first;
            else if (!pred(*last))
                --last;
            else
                break;
        }
        iter_swap(first, last);
        ++first;
    }
}

template <class BidirectionalIterator, class Predicate, class Distance>
BidirectionalIterator __inplace_stable_partition (BidirectionalIterator first,
                                                  BidirectionalIterator last,
                                                  Predicate pred,
                                                  Distance len)
{
    if (len == 1) return pred(*first) ? last : first;
    BidirectionalIterator middle = first;
    advance(middle, len / 2);
    BidirectionalIterator
    first_cut = __inplace_stable_partition(first, middle, pred, len / 2);
    BidirectionalIterator
    second_cut = __inplace_stable_partition(middle, last, pred, len - len / 2);
    rotate(first_cut, middle, second_cut);
    __initialize(len, Distance(0));
    distance(middle, second_cut, len);
    advance(first_cut, len);
    return first_cut;
}

template <class BidirectionalIterator, class Pointer, class Predicate,
          class Distance, class T>
BidirectionalIterator __stable_partition_adaptive (BidirectionalIterator first,
                                                   BidirectionalIterator last,
                                                   Predicate pred, Distance len,
                                                   Pointer buffer,
                                                   Distance buffer_size,
                                                   Distance& fill_pointer, T*)
{
    if (len <= buffer_size)
    {
        len = 0;
        BidirectionalIterator result1 = first;
        Pointer result2 = buffer;
        while (first != last && len < fill_pointer)
        {
            if (pred(*first))
                *result1++ = *first++;
            else
            {
                *result2++ = *first++;
                ++len;
            }
        }
        if (first != last)
        {
            raw_storage_iterator<Pointer, T> result3(result2);
            while (first != last)
            {
                if (pred(*first))
                    *result1++ = *first++;
                else
                {
                    *result3++ = *first++;
                    ++len;
                }
            }
            fill_pointer = len;
        }
        copy(buffer, buffer + len, result1);
        return result1;
    }
    BidirectionalIterator middle = first;
    advance(middle, len / 2);
    BidirectionalIterator first_cut = __stable_partition_adaptive
     (first, middle, pred, len / 2, buffer, buffer_size, fill_pointer, (T*)0);
    BidirectionalIterator second_cut = __stable_partition_adaptive
     (middle, last, pred, len-len/2, buffer, buffer_size, fill_pointer, (T*)0);
    rotate(first_cut, middle, second_cut);
    __initialize(len, Distance(0));
    distance(middle, second_cut, len);
    advance(first_cut, len);
    return first_cut;
}

template <class BidirectionalIterator, class Predicate, class Pointer,
          class Distance>
BidirectionalIterator __stable_partition (BidirectionalIterator first,
                                          BidirectionalIterator last,
                                          Predicate pred, Distance len,
                                          pair<Pointer, Distance> p)
{
    if (p.first == 0)
        return __inplace_stable_partition(first, last, pred, len);
    Distance fill_pointer = 0;
    BidirectionalIterator result =
        __stable_partition_adaptive(first, last, pred, len, p.first,
                                    p.second, fill_pointer,
                                    _RWSTD_VALUE_TYPE(first));
    destroy(p.first, p.first + fill_pointer);
    return_temporary_buffer(p.first);
    return result;
}

//
// Sorting and related operations.
//

template <class RandomAccessIterator, class T>
RandomAccessIterator __unguarded_partition (RandomAccessIterator first,
                                            RandomAccessIterator last,
                                            T pivot)
{
    while (true)
    {
        while (*first < pivot) ++first;
        --last;
        while (pivot < *last) --last;
        if (!(first < last)) return first;
        iter_swap(first, last);
        ++first;
    }
}

template <class RandomAccessIterator, class T, class Compare>
RandomAccessIterator __unguarded_partition (RandomAccessIterator first,
                                            RandomAccessIterator last,
                                            T pivot, Compare _RWSTD_COMP)
{
    while (true)
    {
        while (_RWSTD_COMP(*first, pivot)) ++first;
        --last;
        while (_RWSTD_COMP(pivot, *last)) --last;
        if (!(first < last)) return first;
        iter_swap(first, last);
        ++first;
    }
}

const int __stl_threshold = 16;

template <class RandomAccessIterator, class T>
void __quick_sort_loop_aux (RandomAccessIterator first,
                            RandomAccessIterator last, T*)
{
    while (last - first > __stl_threshold)
    {
        RandomAccessIterator cut = __unguarded_partition
            (first, last, T(__median(*first, *(first + (last - first)/2),
                         *(last - 1))));
        if (cut - first >= last - cut)
        {
            __quick_sort_loop(cut, last);
            last = cut;
        }
        else
        {
            __quick_sort_loop(first, cut);
            first = cut;
        }
    }
}

template <class RandomAccessIterator, class T, class Compare>
void __quick_sort_loop_aux (RandomAccessIterator first,
                            RandomAccessIterator last, T*, Compare _RWSTD_COMP)
{
    while (last - first > __stl_threshold)
    {
        RandomAccessIterator cut = __unguarded_partition
            (first, last, T(__median(*first, *(first + (last - first)/2),
                       *(last - 1), _RWSTD_COMP)), _RWSTD_COMP);
        if (cut - first >= last - cut)
        {
            __quick_sort_loop(cut, last, _RWSTD_COMP);
            last = cut;
        }
        else
        {
            __quick_sort_loop(first, cut, _RWSTD_COMP);
            first = cut;
        }
    }
}



template <class RandomAccessIterator, class T>
void __unguarded_linear_insert (RandomAccessIterator last, T value)
{
    RandomAccessIterator next = last;
    --next;
    while (value < *next)
    {
        *last = *next;
        last = next--;
    }
    *last = value;
}

template <class RandomAccessIterator, class T, class Compare>
void __unguarded_linear_insert (RandomAccessIterator last,T value,Compare _RWSTD_COMP)
{
    RandomAccessIterator next = last;
    --next;
    while (_RWSTD_COMP(value , *next))
    {
        *last = *next;
        last = next--;
    }
    *last = value;
}

template <class RandomAccessIterator>
void __insertion_sort (RandomAccessIterator first, RandomAccessIterator last)
{
    if (!(first == last))
        for (RandomAccessIterator i = first + 1; i != last; ++i)
            __linear_insert(first, i, _RWSTD_VALUE_TYPE(first));
}

template <class RandomAccessIterator, class Compare>
void __insertion_sort (RandomAccessIterator first,
                       RandomAccessIterator last, Compare _RWSTD_COMP)
{
    if (!(first == last))
        for (RandomAccessIterator i = first + 1; i != last; ++i)
            __linear_insert(first, i, _RWSTD_VALUE_TYPE(first), _RWSTD_COMP);
}

template <class RandomAccessIterator, class T>
void __unguarded_insertion_sort_aux (RandomAccessIterator first,
                                     RandomAccessIterator last, T*)
{
    for (RandomAccessIterator i = first; i != last; ++i)
        __unguarded_linear_insert(i, T(*i));
}

template <class RandomAccessIterator, class T, class Compare>
void __unguarded_insertion_sort_aux (RandomAccessIterator first,
                                     RandomAccessIterator last,
                                     T*, Compare _RWSTD_COMP)
{
    for (RandomAccessIterator i = first; i != last; ++i)
        __unguarded_linear_insert(i, T(*i), _RWSTD_COMP);
}


template <class RandomAccessIterator>
void __final_insertion_sort (RandomAccessIterator first,
                                    RandomAccessIterator last)
{
    if (last - first > __stl_threshold)
    {
        __insertion_sort(first, first + __stl_threshold);
        __unguarded_insertion_sort(first + __stl_threshold, last);
    }
    else
        __insertion_sort(first, last);
}

template <class RandomAccessIterator, class Compare>
void __final_insertion_sort (RandomAccessIterator first,
                             RandomAccessIterator last, Compare _RWSTD_COMP)
{
    if (last - first > __stl_threshold)
    {
        __insertion_sort(first, first + __stl_threshold, _RWSTD_COMP);
        __unguarded_insertion_sort(first + __stl_threshold, last, _RWSTD_COMP);
    }
    else
        __insertion_sort(first, last, _RWSTD_COMP);
}

template <class RandomAccessIterator1, class RandomAccessIterator2,
          class Distance>
void __merge_sort_loop (RandomAccessIterator1 first,
                        RandomAccessIterator1 last,
                        RandomAccessIterator2 result, Distance step_size)
{
    Distance two_step = 2 * step_size;

    while (last - first >= two_step)
    {
        result = merge(first, first + step_size,
                       first + step_size, first + two_step, result);
        first += two_step;
    }
    step_size = min(Distance(last - first), step_size);

    merge(first, first + step_size, first + step_size, last, result);
}

template <class RandomAccessIterator1, class RandomAccessIterator2,
          class Distance, class Compare>
void __merge_sort_loop (RandomAccessIterator1 first,
                        RandomAccessIterator1 last,
                        RandomAccessIterator2 result, Distance step_size,
                        Compare _RWSTD_COMP)
{
    Distance two_step = 2 * step_size;

    while (last - first >= two_step)
    {
        result = merge(first, first + step_size,
                       first + step_size, first + two_step, result, _RWSTD_COMP);
        first += two_step;
    }
    step_size = min(Distance(last - first), step_size);

    merge(first, first + step_size, first + step_size, last, result, _RWSTD_COMP);
}

const int __stl_chunk_size = 7;

template <class RandomAccessIterator, class Distance>
void __chunk_insertion_sort (RandomAccessIterator first,
                             RandomAccessIterator last, Distance chunk_size)
{
    while (last - first >= chunk_size)
    {
        __insertion_sort(first, first + chunk_size);
        first += chunk_size;
    }
    __insertion_sort(first, last);
}

template <class RandomAccessIterator, class Distance, class Compare>
void __chunk_insertion_sort (RandomAccessIterator first,
                             RandomAccessIterator last,
                             Distance chunk_size, Compare _RWSTD_COMP)
{
    while (last - first >= chunk_size)
    {
        __insertion_sort(first, first + chunk_size, _RWSTD_COMP);
        first += chunk_size;
    }
    __insertion_sort(first, last, _RWSTD_COMP);
}

template <class RandomAccessIterator, class Pointer, class Distance, class T>
void __merge_sort_with_buffer (RandomAccessIterator first,
                               RandomAccessIterator last,
                               Pointer buffer, Distance*, T*)
{
    Distance len = last - first;
    Pointer buffer_last = buffer + len;

    Distance step_size = __stl_chunk_size;
    __chunk_insertion_sort(first, last, step_size);

    while (step_size < len)
    {
        __merge_sort_loop(first, last, buffer, step_size);
        step_size *= 2;
        __merge_sort_loop(buffer, buffer_last, first, step_size);
        step_size *= 2;
    }
}

template <class RandomAccessIterator, class Pointer, class Distance, class T,
          class Compare>
void __merge_sort_with_buffer (RandomAccessIterator first,
                               RandomAccessIterator last, Pointer buffer,
                               Distance*, T*, Compare _RWSTD_COMP)
{
    Distance len = last - first;
    Pointer buffer_last = buffer + len;

    Distance step_size = __stl_chunk_size;
    __chunk_insertion_sort(first, last, step_size, _RWSTD_COMP);

    while (step_size < len)
    {
        __merge_sort_loop(first, last, buffer, step_size, _RWSTD_COMP);
        step_size *= 2;
        __merge_sort_loop(buffer, buffer_last, first, step_size, _RWSTD_COMP);
        step_size *= 2;
    }
}

template <class RandomAccessIterator, class Pointer, class Distance, class T>
void __stable_sort_adaptive (RandomAccessIterator first,
                             RandomAccessIterator last, Pointer buffer,
                             Distance buffer_size, T*)
{
    Distance len = (last - first + 1) / 2;
    RandomAccessIterator middle = first + len;
    if (len > buffer_size)
    {
      __stable_sort_adaptive(first, middle, buffer, buffer_size,
                 _RWSTD_STATIC_CAST(T*,0));
      __stable_sort_adaptive(middle, last, buffer, buffer_size,
                 _RWSTD_STATIC_CAST(T*,0));
    }
    else
      {
        __merge_sort_with_buffer(first, middle, buffer,
                 _RWSTD_STATIC_CAST(Distance*,0),
                 _RWSTD_STATIC_CAST(T*,0));
        __merge_sort_with_buffer(middle, last, buffer,
                 _RWSTD_STATIC_CAST(Distance*,0),
                 _RWSTD_STATIC_CAST(T*,0));
    }
    __merge_adaptive(first, middle, last, Distance(middle - first),
             Distance(last - middle), buffer, buffer_size, _RWSTD_STATIC_CAST(T*,0));
}

template <class RandomAccessIterator, class Pointer, class Distance, class T,
          class Compare>
void __stable_sort_adaptive (RandomAccessIterator first,
                             RandomAccessIterator last, Pointer buffer,
                             Distance buffer_size, T*, Compare _RWSTD_COMP)
{
    Distance len = (last - first + 1) / 2;
    RandomAccessIterator middle = first + len;
    if (len > buffer_size)
    {
        __stable_sort_adaptive(first, middle, buffer, buffer_size,_RWSTD_STATIC_CAST(T*,0),_RWSTD_COMP);
        __stable_sort_adaptive(middle, last, buffer, buffer_size, _RWSTD_STATIC_CAST(T*,0),_RWSTD_COMP);
    }
    else
    {
      __merge_sort_with_buffer(first, middle, buffer, _RWSTD_STATIC_CAST(Distance*,0),
                   _RWSTD_STATIC_CAST(T*,0), _RWSTD_COMP);
      __merge_sort_with_buffer(middle, last, buffer, _RWSTD_STATIC_CAST(Distance*,0),
                   _RWSTD_STATIC_CAST(T*,0), _RWSTD_COMP);
    }
    __merge_adaptive(first, middle, last, Distance(middle - first),
                     Distance(last-middle), buffer, buffer_size, _RWSTD_STATIC_CAST(T*,0),_RWSTD_COMP);
}

template <class RandomAccessIterator, class T>
void __partial_sort (RandomAccessIterator first, RandomAccessIterator middle,
                     RandomAccessIterator last, T*)
{
    make_heap(first, middle);
    for (RandomAccessIterator i = middle; i < last; ++i)
        if (*i < *first)
            __pop_heap(first, middle, i, T(*i), distance_type(first));
    sort_heap(first, middle);
}

template <class RandomAccessIterator, class T, class Compare>
void __partial_sort (RandomAccessIterator first, RandomAccessIterator middle,
                     RandomAccessIterator last, T*, Compare _RWSTD_COMP)
{
    make_heap(first, middle, _RWSTD_COMP);
    for (RandomAccessIterator i = middle; i < last; ++i)
        if (_RWSTD_COMP(*i,*first))
            __pop_heap(first, middle, i, T(*i), _RWSTD_COMP, distance_type(first));
    sort_heap(first, middle, _RWSTD_COMP);
}

template <class InputIterator, class RandomAccessIterator, class Distance,
          class T>
RandomAccessIterator __partial_sort_copy (InputIterator first,
                                          InputIterator last,
                                          RandomAccessIterator result_first,
                                          RandomAccessIterator result_last,
                                          Distance*, T*)
{
    if (result_first == result_last) return result_last;
    RandomAccessIterator result_real_last = result_first;
    while(first != last && result_real_last != result_last)
        *result_real_last++ = *first++;
    make_heap(result_first, result_real_last);
    while (first != last)
    {
        if (*first < *result_first)
            __adjust_heap(result_first, Distance(0),
                          Distance(result_real_last - result_first),
                          T(*first));
        ++first;
    }
    sort_heap(result_first, result_real_last);
    return result_real_last;
}

template <class InputIterator, class RandomAccessIterator, class Compare,
          class Distance, class T>
RandomAccessIterator __partial_sort_copy (InputIterator first,
                                          InputIterator last,
                                          RandomAccessIterator result_first,
                                          RandomAccessIterator result_last,
                                          Compare _RWSTD_COMP, Distance*, T*)
{
    if (result_first == result_last) return result_last;
    RandomAccessIterator result_real_last = result_first;
    while(first != last && result_real_last != result_last)
        *result_real_last++ = *first++;
    make_heap(result_first, result_real_last, _RWSTD_COMP);
    while (first != last)
    {
        if (_RWSTD_COMP(*first,*result_first))
            __adjust_heap(result_first, Distance(0),
                          Distance(result_real_last - result_first), T(*first),
                          _RWSTD_COMP);
        ++first;
    }
    sort_heap(result_first, result_real_last, _RWSTD_COMP);
    return result_real_last;
}

template <class RandomAccessIterator, class T>
void __nth_element (RandomAccessIterator first, RandomAccessIterator nth,
                    RandomAccessIterator last, T*)
{
    while (last - first > 3)
    {
        RandomAccessIterator cut = __unguarded_partition
            (first, last, T(__median(*first, *(first + (last - first)/2),
                         *(last - 1))));
        if (cut <= nth)
            first = cut;
        else
            last = cut;
    }
    __insertion_sort(first, last);
}

template <class RandomAccessIterator, class T, class Compare>
void __nth_element (RandomAccessIterator first, RandomAccessIterator nth,
                    RandomAccessIterator last, T*, Compare _RWSTD_COMP)
{
    while (last - first > 3)
    {
        RandomAccessIterator cut = __unguarded_partition
            (first, last, T(__median(*first, *(first + (last - first)/2),
                     *(last - 1), _RWSTD_COMP)), _RWSTD_COMP);
        if (cut <= nth)
            first = cut;
        else
            last = cut;
        }
    __insertion_sort(first, last, _RWSTD_COMP);
}

//
// Binary search.
//

template <class ForwardIterator, class T, class Distance>
ForwardIterator __lower_bound (ForwardIterator first, ForwardIterator last,
                               const T& value, Distance*,
                               forward_iterator_tag)
{
    Distance len;
    __initialize(len, Distance(0));
    distance(first, last, len);
    Distance half;
    ForwardIterator middle;

    while (len > 0)
    {
        half = len / 2;
        middle = first;
        advance(middle, half);
        if (*middle < value)
        {
            first = middle;
            ++first;
            len = len - half - 1;
        }
        else
            len = half;
    }
    return first;
}

template <class RandomAccessIterator, class T, class Distance>
RandomAccessIterator __lower_bound (RandomAccessIterator first,
                                    RandomAccessIterator last, const T& value,
                                    Distance*, random_access_iterator_tag)
{
    Distance len = last - first;
    Distance half;
    RandomAccessIterator middle;

    while (len > 0)
    {
        half = len / 2;
        middle = first + half;
        if (*middle < value)
        {
            first = middle + 1;
            len = len - half - 1;
        }
        else
            len = half;
    }
    return first;
}

template <class ForwardIterator, class T, class Compare, class Distance>
ForwardIterator __lower_bound (ForwardIterator first, ForwardIterator last,
                               const T& value, Compare _RWSTD_COMP, Distance*,
                               forward_iterator_tag)
{
    Distance len;
    __initialize(len, Distance(0));
    distance(first, last, len);
    Distance half;
    ForwardIterator middle;

    while (len > 0)
    {
        half = len / 2;
        middle = first;
        advance(middle, half);
        if (_RWSTD_COMP(*middle, value))
        {
            first = middle;
            ++first;
            len = len - half - 1;
        }
        else
            len = half;
    }
    return first;
}

template <class RandomAccessIterator, class T, class Compare, class Distance>
RandomAccessIterator __lower_bound (RandomAccessIterator first,
                                    RandomAccessIterator last,
                                    const T& value, Compare _RWSTD_COMP, Distance*,
                                    random_access_iterator_tag)
{
    Distance len = last - first;
    Distance half;
    RandomAccessIterator middle;

    while (len > 0)
    {
        half = len / 2;
        middle = first + half;
        if (_RWSTD_COMP(*middle, value))
        {
            first = middle + 1;
            len = len - half - 1;
        }
        else
            len = half;
    }
    return first;
}

template <class ForwardIterator, class T, class Distance>
ForwardIterator __upper_bound (ForwardIterator first, ForwardIterator last,
                               const T& value, Distance*,
                               forward_iterator_tag)
{
    Distance len;
    __initialize(len, Distance(0));
    distance(first, last, len);
    Distance half;
    ForwardIterator middle;

    while (len > 0)
    {
        half = len / 2;
        middle = first;
        advance(middle, half);
        if (value < *middle)
            len = half;
        else
        {
            first = middle;
            ++first;
            len = len - half - 1;
        }
    }
    return first;
}

template <class RandomAccessIterator, class T, class Distance>
RandomAccessIterator __upper_bound (RandomAccessIterator first,
                                    RandomAccessIterator last, const T& value,
                                    Distance*, random_access_iterator_tag)
{
    Distance len = last - first;
    Distance half;
    RandomAccessIterator middle;

    while (len > 0)
    {
        half = len / 2;
        middle = first + half;
        if (value < *middle)
            len = half;
        else
        {
            first = middle + 1;
            len = len - half - 1;
        }
    }
    return first;
}

template <class ForwardIterator, class T, class Compare, class Distance>
ForwardIterator __upper_bound (ForwardIterator first, ForwardIterator last,
                               const T& value, Compare _RWSTD_COMP, Distance*,
                               forward_iterator_tag)
{
    Distance len;
    __initialize(len, Distance(0));
    distance(first, last, len);
    Distance half;
    ForwardIterator middle;

    while (len > 0)
    {
        half = len / 2;
        middle = first;
        advance(middle, half);
        if (_RWSTD_COMP(value, *middle))
            len = half;
        else {
            first = middle;
            ++first;
            len = len - half - 1;
        }
    }
    return first;
}

template <class RandomAccessIterator, class T, class Compare, class Distance>
RandomAccessIterator __upper_bound (RandomAccessIterator first,
                                    RandomAccessIterator last,
                                    const T& value, Compare _RWSTD_COMP, Distance*,
                                    random_access_iterator_tag)
{
    Distance len = last - first;
    Distance half;
    RandomAccessIterator middle;

    while (len > 0)
    {
        half = len / 2;
        middle = first + half;
        if (_RWSTD_COMP(value, *middle))
            len = half;
        else {
            first = middle + 1;
            len = len - half - 1;
        }
    }
    return first;
}

template <class ForwardIterator, class T, class Distance>
pair<ForwardIterator, ForwardIterator>
__equal_range (ForwardIterator first, ForwardIterator last, const T& value,
               Distance*, forward_iterator_tag)
{
    Distance len;
    __initialize(len, Distance(0));
    distance(first, last, len);
    Distance half;
    ForwardIterator middle, left, right;

    while (len > 0)
    {
        half = len / 2;
        middle = first;
        advance(middle, half);
        if (*middle < value)
        {
            first = middle;
            ++first;
            len = len - half - 1;
        }
        else if (value < *middle)
            len = half;
        else
        {
            left = lower_bound(first, middle, value);
            advance(first, len);
            right = upper_bound(++middle, first, value);
            pair<ForwardIterator, ForwardIterator> tmp(left, right);
            return tmp;
        }
    }
    pair<ForwardIterator, ForwardIterator> tmp(first, first);
    return tmp;
}

template <class RandomAccessIterator, class T, class Distance>
pair<RandomAccessIterator, RandomAccessIterator>
__equal_range (RandomAccessIterator first, RandomAccessIterator last,
               const T& value, Distance*, random_access_iterator_tag)
{
    Distance len = last - first;
    Distance half;
    RandomAccessIterator middle, left, right;

    while (len > 0)
    {
        half = len / 2;
        middle = first + half;
        if (*middle < value)
        {
            first = middle + 1;
            len = len - half - 1;
        }
        else if (value < *middle)
            len = half;
        else
        {
            left = lower_bound(first, middle, value);
            right = upper_bound(++middle, first + len, value);
            pair<RandomAccessIterator,RandomAccessIterator> tmp(left,right);
            return tmp;
        }
    }
    pair<RandomAccessIterator, RandomAccessIterator> tmp(first, first);
    return tmp;
}

template <class ForwardIterator, class T, class Compare, class Distance>
pair<ForwardIterator, ForwardIterator>
__equal_range (ForwardIterator first, ForwardIterator last, const T& value,
               Compare _RWSTD_COMP, Distance*, forward_iterator_tag)
{
    Distance len;
    __initialize(len, Distance(0));
    distance(first, last, len);
    Distance half;
    ForwardIterator middle, left, right;

    while (len > 0)
    {
        half = len / 2;
        middle = first;
        advance(middle, half);
        if (_RWSTD_COMP(*middle, value))
        {
            first = middle;
            ++first;
            len = len - half - 1;
        }
        else if (_RWSTD_COMP(value, *middle))
            len = half;
        else
        {
            left = lower_bound(first, middle, value, _RWSTD_COMP);
            advance(first, len);
            right = upper_bound(++middle, first, value, _RWSTD_COMP);
            pair<ForwardIterator, ForwardIterator> tmp(left, right);
            return tmp;
        }
    }
    pair<ForwardIterator, ForwardIterator> tmp(first, first);
    return tmp;
}

template <class RandomAccessIterator, class T, class Compare, class Distance>
pair<RandomAccessIterator, RandomAccessIterator>
__equal_range (RandomAccessIterator first, RandomAccessIterator last,
               const T& value, Compare _RWSTD_COMP, Distance*,
               random_access_iterator_tag)
{
    Distance len = last - first;
    Distance half;
    RandomAccessIterator middle, left, right;

    while (len > 0)
    {
        half = len / 2;
        middle = first + half;
        if (_RWSTD_COMP(*middle, value))
        {
            first = middle + 1;
            len = len - half - 1;
        }
        else if (_RWSTD_COMP(value, *middle))
            len = half;
        else
        {
            left = lower_bound(first, middle, value, _RWSTD_COMP);
            right = upper_bound(++middle, first + len, value, _RWSTD_COMP);
            pair<RandomAccessIterator,RandomAccessIterator> tmp(left, right);
            return tmp;
        }
    }
    pair<RandomAccessIterator, RandomAccessIterator> tmp(first, first);
    return tmp;
}

//
// Merge
//

template <class InputIterator1, class InputIterator2, class OutputIterator>
OutputIterator merge (InputIterator1 first1, InputIterator1 last1,
                      InputIterator2 first2, InputIterator2 last2,
                      OutputIterator result)
{
    while (first1 != last1 && first2 != last2)
    {
        if (*first2 < *first1)
            *result++ = *first2++;
        else
            *result++ = *first1++;
    }
    return copy(first2, last2, copy(first1, last1, result));
}

template <class InputIterator1, class InputIterator2, class OutputIterator,
          class Compare>
OutputIterator merge (InputIterator1 first1, InputIterator1 last1,
                      InputIterator2 first2, InputIterator2 last2,
                      OutputIterator result, Compare _RWSTD_COMP)
{
    while (first1 != last1 && first2 != last2)
    {
        if (_RWSTD_COMP(*first2, *first1))
            *result++ = *first2++;
        else
            *result++ = *first1++;
    }
    return copy(first2, last2, copy(first1, last1, result));
}

template <class BidirectionalIterator, class Distance>
void __merge_without_buffer (BidirectionalIterator first,
                             BidirectionalIterator middle,
                             BidirectionalIterator last,
                             Distance len1, Distance len2)
{
    if (len1 == 0 || len2 == 0) return;
    if (len1 + len2 == 2)
    {
        if (*middle < *first) iter_swap(first, middle);
        return;
    }
    BidirectionalIterator first_cut = first;
    BidirectionalIterator second_cut = middle;
    Distance len11;
    __initialize(len11, Distance(0));
    Distance len22;
    __initialize(len22, Distance(0));
    if (len1 > len2)
    {
        len11 = len1 / 2;
        advance(first_cut, len11);
        second_cut = lower_bound(middle, last, *first_cut);
        distance(middle, second_cut, len22);
    }
    else
    {
        len22 = len2 / 2;
        advance(second_cut, len22);
        first_cut = upper_bound(first, middle, *second_cut);
        distance(first, first_cut, len11);
    }
    rotate(first_cut, middle, second_cut);
    BidirectionalIterator new_middle = first_cut;
    advance(new_middle, len22);
    __merge_without_buffer(first, first_cut, new_middle, len11, len22);
    __merge_without_buffer(new_middle, second_cut, last, len1 - len11,
                           len2 - len22);
}

template <class BidirectionalIterator, class Distance, class Compare>
void __merge_without_buffer (BidirectionalIterator first,
                             BidirectionalIterator middle,
                             BidirectionalIterator last,
                             Distance len1, Distance len2, Compare _RWSTD_COMP)
{
    if (len1 == 0 || len2 == 0) return;
    if (len1 + len2 == 2)
    {
        if (_RWSTD_COMP(*middle, *first)) iter_swap(first, middle);
        return;
    }
    BidirectionalIterator first_cut = first;
    BidirectionalIterator second_cut = middle;
    Distance len11;
    __initialize(len11, Distance(0));
    Distance len22;
    __initialize(len22, Distance(0));
    if (len1 > len2)
    {
        len11 = len1 / 2;
        advance(first_cut, len11);
        second_cut = lower_bound(middle, last, *first_cut, _RWSTD_COMP);
        distance(middle, second_cut, len22);
    }
    else
    {
        len22 = len2 / 2;
        advance(second_cut, len22);
        first_cut = upper_bound(first, middle, *second_cut, _RWSTD_COMP);
        distance(first, first_cut, len11);
    }
    rotate(first_cut, middle, second_cut);
    BidirectionalIterator new_middle = first_cut;
    advance(new_middle, len22);
    __merge_without_buffer(first, first_cut, new_middle, len11, len22, _RWSTD_COMP);
    __merge_without_buffer(new_middle, second_cut, last, len1 - len11,
                           len2 - len22, _RWSTD_COMP);
}

template <class BidirectionalIterator1, class BidirectionalIterator2,
          class Distance>
BidirectionalIterator1 __rotate_adaptive (BidirectionalIterator1 first,
                                          BidirectionalIterator1 middle,
                                          BidirectionalIterator1 last,
                                          Distance len1, Distance len2,
                                          BidirectionalIterator2 buffer,
                                          Distance buffer_size)
{
    BidirectionalIterator2 buffer_end;
    if (len1 > len2 && len2 <= buffer_size)
    {
        buffer_end = copy(middle, last, buffer);
        copy_backward(first, middle, last);
        return copy(buffer, buffer_end, first);
    }
    else if (len1 <= buffer_size)
    {
        buffer_end = copy(first, middle, buffer);
        copy(middle, last, first);
        return copy_backward(buffer, buffer_end, last);
    }
    else
    {
        rotate(first, middle, last);
        advance(first, len2);
        return first;
    }
}

template <class BidirectionalIterator1, class BidirectionalIterator2,
          class BidirectionalIterator3>
BidirectionalIterator3 __merge_backward (BidirectionalIterator1 first1,
                                         BidirectionalIterator1 last1,
                                         BidirectionalIterator2 first2,
                                         BidirectionalIterator2 last2,
                                         BidirectionalIterator3 result)
{
    if (first1 == last1) return copy_backward(first2, last2, result);
    if (first2 == last2) return copy_backward(first1, last1, result);
    --last1;
    --last2;
    while (true)
    {
        if (*last2 < *last1)
        {
            *--result = *last1;
            if (first1 == last1) return copy_backward(first2, ++last2, result);
            --last1;
        }
        else
        {
            *--result = *last2;
            if (first2 == last2) return copy_backward(first1, ++last1, result);
            --last2;
        }
    }
}

template <class BidirectionalIterator1, class BidirectionalIterator2,
          class BidirectionalIterator3, class Compare>
BidirectionalIterator3 __merge_backward (BidirectionalIterator1 first1,
                                         BidirectionalIterator1 last1,
                                         BidirectionalIterator2 first2,
                                         BidirectionalIterator2 last2,
                                         BidirectionalIterator3 result,
                                         Compare _RWSTD_COMP)
{
    if (first1 == last1) return copy_backward(first2, last2, result);
    if (first2 == last2) return copy_backward(first1, last1, result);
    --last1;
    --last2;
    while (true)
    {
        if (_RWSTD_COMP(*last2, *last1))
        {
            *--result = *last1;
            if (first1 == last1) return copy_backward(first2, ++last2, result);
            --last1;
        }
        else
        {
            *--result = *last2;
            if (first2 == last2) return copy_backward(first1, ++last1, result);
            --last2;
        }
    }
}

template <class BidirectionalIterator, class Distance, class Pointer, class T>
void __merge_adaptive (BidirectionalIterator first,
                       BidirectionalIterator middle,
                       BidirectionalIterator last, Distance len1,Distance len2,
                       Pointer buffer, Distance buffer_size, T*)
{
    if (len1 <= len2 && len1 <= buffer_size)
    {
        Pointer end_buffer = copy(first, middle, buffer);
        merge(buffer, end_buffer, middle, last, first);
    }
    else if (len2 <= buffer_size)
    {
        Pointer end_buffer = copy(middle, last, buffer);
        __merge_backward(first, middle, buffer, end_buffer, last);
    }
    else
    {
        BidirectionalIterator first_cut = first;
        BidirectionalIterator second_cut = middle;
        Distance len11;
        __initialize(len11, Distance(0));
        Distance len22;
        __initialize(len22, Distance(0));
        if (len1 > len2)
        {
            len11 = len1 / 2;
            advance(first_cut, len11);
            second_cut = lower_bound(middle, last, *first_cut);
            distance(middle, second_cut, len22);
        }
        else
        {
            len22 = len2 / 2;
            advance(second_cut, len22);
            first_cut = upper_bound(first, middle, *second_cut);
            distance(first, first_cut, len11);
        }
        BidirectionalIterator new_middle =
      __rotate_adaptive(first_cut, middle, second_cut, len1 - len11,
                len22, buffer, buffer_size);
    __merge_adaptive(first, first_cut, new_middle, len11, len22, buffer,
                         buffer_size, _RWSTD_STATIC_CAST(T*,0));
        __merge_adaptive(new_middle, second_cut, last, len1 - len11,
                         len2 - len22, buffer, buffer_size, _RWSTD_STATIC_CAST(T*,0));
    }
}

template <class BidirectionalIterator, class Distance, class Pointer, class T,
          class Compare>
void __merge_adaptive (BidirectionalIterator first,
                       BidirectionalIterator middle,
                       BidirectionalIterator last, Distance len1,Distance len2,
                       Pointer buffer, Distance buffer_size, T*, Compare _RWSTD_COMP)
{
    if (len1 <= len2 && len1 <= buffer_size)
    {
        Pointer end_buffer = copy(first, middle, buffer);
        merge(buffer, end_buffer, middle, last, first, _RWSTD_COMP);
    }
    else if (len2 <= buffer_size)
    {
        Pointer end_buffer = copy(middle, last, buffer);
        __merge_backward(first, middle, buffer, end_buffer, last, _RWSTD_COMP);
    }
    else
    {
        BidirectionalIterator first_cut = first;
        BidirectionalIterator second_cut = middle;
        Distance len11;
        __initialize(len11, Distance(0));
        Distance len22;
        __initialize(len22, Distance(0));
        if (len1 > len2)
        {
            len11 = len1 / 2;
            advance(first_cut, len11);
            second_cut = lower_bound(middle, last, *first_cut, _RWSTD_COMP);
            distance(middle, second_cut, len22);
        }
        else
        {
            len22 = len2 / 2;
            advance(second_cut, len22);
            first_cut = upper_bound(first, middle, *second_cut, _RWSTD_COMP);
            distance(first, first_cut, len11);
        }
        BidirectionalIterator new_middle =
            __rotate_adaptive(first_cut, middle, second_cut, len1 - len11,
                              len22, buffer, buffer_size);
        __merge_adaptive(first, first_cut, new_middle, len11, len22, buffer,
                         buffer_size, _RWSTD_STATIC_CAST(T*,0), _RWSTD_COMP);
        __merge_adaptive(new_middle, second_cut, last, len1 - len11,
                         len2 - len22, buffer, buffer_size, _RWSTD_STATIC_CAST(T*,0), _RWSTD_COMP);
    }
}

template <class BidirectionalIterator, class Distance, class Pointer, class T>
void __inplace_merge (BidirectionalIterator first,
                      BidirectionalIterator middle,
                      BidirectionalIterator last, Distance len1,
                      Distance len2, pair<Pointer, Distance> p, T*)
{
    if (p.first == 0)
        __merge_without_buffer(first, middle, last, len1, len2);
    else
    {
        Distance len = min(p.second, len1 + len2);
        fill_n(raw_storage_iterator<Pointer, T>(p.first), len, *first);
        __merge_adaptive(first, middle, last, len1, len2, p.first,
                         p.second, _RWSTD_STATIC_CAST(T*,0));
        destroy(p.first, p.first + len);
        return_temporary_buffer(p.first);
    }
}

template <class BidirectionalIterator, class Distance, class Pointer, class T,
      class Compare>
void __inplace_merge (BidirectionalIterator first,
                      BidirectionalIterator middle,
                      BidirectionalIterator last, Distance len1,
                      Distance len2, pair<Pointer, Distance> p, T*,
                      Compare _RWSTD_COMP)
{
    if (p.first == 0)
        __merge_without_buffer(first, middle, last, len1, len2, _RWSTD_COMP);
    else
    {
        Distance len = min(p.second, len1 + len2);
        fill_n(raw_storage_iterator<Pointer, T>(p.first), len, *first);
        __merge_adaptive(first, middle, last, len1, len2, p.first,
                         p.second, _RWSTD_STATIC_CAST(T*,0), _RWSTD_COMP);
        destroy(p.first, p.first + len);
        return_temporary_buffer(p.first);
    }
}

//
// Set operations.
//

template <class InputIterator1, class InputIterator2>
bool includes (InputIterator1 first1, InputIterator1 last1,
               InputIterator2 first2, InputIterator2 last2)
{
    while (first1 != last1 && first2 != last2)
    {
        if (*first2 < *first1)
            return false;
        else if(*first1 < *first2)
            ++first1;
        else
            ++first1, ++first2;
    }
    return first2 == last2;
}

template <class InputIterator1, class InputIterator2, class Compare>
bool includes (InputIterator1 first1, InputIterator1 last1,
               InputIterator2 first2, InputIterator2 last2, Compare _RWSTD_COMP)
{
    while (first1 != last1 && first2 != last2)
    {
        if (_RWSTD_COMP(*first2, *first1))
            return false;
        else if(_RWSTD_COMP(*first1, *first2))
            ++first1;
        else
            ++first1, ++first2;
    }
    return first2 == last2;
}

template <class InputIterator1, class InputIterator2, class OutputIterator>
OutputIterator set_union (InputIterator1 first1, InputIterator1 last1,
                          InputIterator2 first2, InputIterator2 last2,
                          OutputIterator result)
{
    while (first1 != last1 && first2 != last2)
    {
        if (*first1 < *first2)
            *result++ = *first1++;
        else if (*first2 < *first1)
            *result++ = *first2++;
        else
        {
            *result++ = *first1++;
            first2++;
        }
    }
    return copy(first2, last2, copy(first1, last1, result));
}

template <class InputIterator1, class InputIterator2, class OutputIterator,
          class Compare>
OutputIterator set_union (InputIterator1 first1, InputIterator1 last1,
                          InputIterator2 first2, InputIterator2 last2,
                          OutputIterator result, Compare _RWSTD_COMP)
{
    while (first1 != last1 && first2 != last2)
    {
        if (_RWSTD_COMP(*first1, *first2))
            *result++ = *first1++;
        else if (_RWSTD_COMP(*first2, *first1))
            *result++ = *first2++;
        else
        {
            *result++ = *first1++;
            ++first2;
        }
    }
    return copy(first2, last2, copy(first1, last1, result));
}

template <class InputIterator1, class InputIterator2, class OutputIterator>
OutputIterator set_intersection (InputIterator1 first1, InputIterator1 last1,
                                 InputIterator2 first2, InputIterator2 last2,
                                 OutputIterator result)
{
    while (first1 != last1 && first2 != last2)
    {
        if (*first1 < *first2)
            ++first1;
        else if (*first2 < *first1)
            ++first2;
        else
        {
            *result++ = *first1++;
            ++first2;
        }
    }
    return result;
}

template <class InputIterator1, class InputIterator2, class OutputIterator,
          class Compare>
OutputIterator set_intersection (InputIterator1 first1, InputIterator1 last1,
                                 InputIterator2 first2, InputIterator2 last2,
                                 OutputIterator result, Compare _RWSTD_COMP)
{
    while (first1 != last1 && first2 != last2)
    {
        if (_RWSTD_COMP(*first1, *first2))
            ++first1;
        else if (_RWSTD_COMP(*first2, *first1))
            ++first2;
        else
        {
            *result++ = *first1++;
            ++first2;
        }
    }
    return result;
}

template <class InputIterator1, class InputIterator2, class OutputIterator>
OutputIterator set_difference (InputIterator1 first1, InputIterator1 last1,
                               InputIterator2 first2, InputIterator2 last2,
                               OutputIterator result)
{
    while (first1 != last1 && first2 != last2)
    {
        if (*first1 < *first2)
            *result++ = *first1++;
        else if (*first2 < *first1)
            ++first2;
        else
        {
            ++first1;
            ++first2;
        }
    }
    return copy(first1, last1, result);
}

template <class InputIterator1, class InputIterator2, class OutputIterator,
          class Compare>
OutputIterator set_difference (InputIterator1 first1, InputIterator1 last1,
                               InputIterator2 first2, InputIterator2 last2,
                               OutputIterator result, Compare _RWSTD_COMP)
{
    while (first1 != last1 && first2 != last2)
    {
        if (_RWSTD_COMP(*first1, *first2))
            *result++ = *first1++;
        else if (_RWSTD_COMP(*first2, *first1))
            ++first2;
        else
        {
            ++first1;
            ++first2;
        }
    }
    return copy(first1, last1, result);
}

template <class InputIterator1, class InputIterator2, class OutputIterator>
OutputIterator set_symmetric_difference (InputIterator1 first1,
                                         InputIterator1 last1,
                                         InputIterator2 first2,
                                         InputIterator2 last2,
                                         OutputIterator result)
{
    while (first1 != last1 && first2 != last2)
    {
        if (*first1 < *first2)
            *result++ = *first1++;
        else if (*first2 < *first1)
            *result++ = *first2++;
        else
        {
            ++first1;
            ++first2;
        }
    }
    return copy(first2, last2, copy(first1, last1, result));
}

template <class InputIterator1, class InputIterator2, class OutputIterator,
          class Compare>
OutputIterator set_symmetric_difference (InputIterator1 first1,
                                         InputIterator1 last1,
                                         InputIterator2 first2,
                                         InputIterator2 last2,
                                         OutputIterator result, Compare _RWSTD_COMP)
{
    while (first1 != last1 && first2 != last2)
    {
        if (_RWSTD_COMP(*first1, *first2))
            *result++ = *first1++;
        else if (_RWSTD_COMP(*first2, *first1))
            *result++ = *first2++;
        else
        {
            ++first1;
            ++first2;
        }
    }
    return copy(first2, last2, copy(first1, last1, result));
}

//
// Heap operations.
//

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;
}

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

template <class RandomAccessIterator, class Distance, class T>
void __adjust_heap (RandomAccessIterator first, Distance holeIndex,
                    Distance len, T value)
{
    Distance topIndex = holeIndex;
    Distance secondChild = 2 * holeIndex + 2;
    while (secondChild < len)
    {
        if (*(first + secondChild) < *(first + (secondChild - 1)))
            secondChild--;
        *(first + holeIndex) = *(first + secondChild);
        holeIndex = secondChild;
        secondChild = 2 * (secondChild + 1);
    }
    if (secondChild == len)
    {
        *(first + holeIndex) = *(first + (secondChild - 1));
        holeIndex = secondChild - 1;
    }
    __push_heap(first, holeIndex, topIndex, value);
}

template <class RandomAccessIterator, class Distance, class T, class Compare>
void __adjust_heap (RandomAccessIterator first, Distance holeIndex,
                    Distance len, T value, Compare _RWSTD_COMP)
{
    Distance topIndex = holeIndex;
    Distance secondChild = 2 * holeIndex + 2;
    while (secondChild < len)
    {
        if (_RWSTD_COMP(*(first + secondChild), *(first + (secondChild - 1))))
            secondChild--;
        *(first + holeIndex) = *(first + secondChild);
        holeIndex = secondChild;
        secondChild = 2 * (secondChild + 1);
    }
    if (secondChild == len)
    {
        *(first + holeIndex) = *(first + (secondChild - 1));
        holeIndex = secondChild - 1;
    }
    __push_heap(first, holeIndex, topIndex, value, _RWSTD_COMP);
}

template <class RandomAccessIterator, class T, class Distance>
void __make_heap (RandomAccessIterator first, RandomAccessIterator last, T*,
                  Distance*)
{
    Distance len = last - first;
    Distance parent = (len - 2)/2;
    while (true)
    {
        __adjust_heap(first, parent, len, T(*(first + parent)));
        if (parent == 0) return;
        parent--;
    }
}

template <class RandomAccessIterator, class Compare, class T, class Distance>
void __make_heap (RandomAccessIterator first, RandomAccessIterator last,
                  Compare _RWSTD_COMP, T*, Distance*)
{
    Distance len = last - first;
    Distance parent = (len - 2)/2;
    while (true)
    {
        __adjust_heap(first, parent, len, T(*(first + parent)), _RWSTD_COMP);
        if (parent == 0)
            return;
        parent--;
    }
}

template <class RandomAccessIterator>
void sort_heap (RandomAccessIterator first, RandomAccessIterator last)
{
    while (last - first > 1) pop_heap(first, last--);
}

template <class RandomAccessIterator, class Compare>
void sort_heap (RandomAccessIterator first, RandomAccessIterator last,
                Compare _RWSTD_COMP)
{
    while (last - first > 1) pop_heap(first, last--, _RWSTD_COMP);
}

//
// Minimum and maximum.
//

template <class ForwardIterator>
ForwardIterator min_element (ForwardIterator first, ForwardIterator last)
{
    if (first == last) return first;
    ForwardIterator result = first;
    while (++first != last)
        if (*first < *result) result = first;
    return result;
}

template <class ForwardIterator, class Compare>
ForwardIterator min_element (ForwardIterator first, ForwardIterator last,
                             Compare _RWSTD_COMP)
{
    if (first == last) return first;
    ForwardIterator result = first;
    while (++first != last)
        if (_RWSTD_COMP(*first, *result)) result = first;
    return result;
}

template <class ForwardIterator>
ForwardIterator max_element (ForwardIterator first, ForwardIterator last)
{
    if (first == last) return first;
    ForwardIterator result = first;
    while (++first != last)
        if (*result < *first) result = first;
    return result;
}

template <class ForwardIterator, class Compare>
ForwardIterator max_element (ForwardIterator first, ForwardIterator last,
                             Compare _RWSTD_COMP)
{
    if (first == last) return first;
    ForwardIterator result = first;
    while (++first != last)
        if (_RWSTD_COMP(*result, *first)) result = first;
    return result;
}

template <class InputIterator1, class InputIterator2>
bool lexicographical_compare (InputIterator1 first1, InputIterator1 last1,
                              InputIterator2 first2, InputIterator2 last2)
{
    while (first1 != last1 && first2 != last2)
    {
        if (*first1 < *first2)     return true;
        if (*first2++ < *first1++) return false;
    }
    return first1 == last1 && first2 != last2;
}

template <class InputIterator1, class InputIterator2, class Compare>
bool lexicographical_compare(InputIterator1 first1, InputIterator1 last1,
                             InputIterator2 first2, InputIterator2 last2,
                             Compare _RWSTD_COMP)
{
    while (first1 != last1 && first2 != last2)
    {
        if (_RWSTD_COMP(*first1, *first2))     return true;
        if (_RWSTD_COMP(*first2++, *first1++)) return false;
    }
    return first1 == last1 && first2 != last2;
}

//
// Permutations.
//

template <class BidirectionalIterator>
bool next_permutation (BidirectionalIterator first,
                       BidirectionalIterator last)
{
    if (first == last) return false;
    BidirectionalIterator i = first;
    ++i;
    if (i == last) return false;
    i = last;
    --i;

    for (;;)
    {
        BidirectionalIterator ii = i--;
        if (*i < *ii)
        {
            BidirectionalIterator j = last;
            while (!(*i < *--j))
                ;
            iter_swap(i, j);
            reverse(ii, last);
            return true;
        }
        if (i == first)
        {
            reverse(first, last);
            return false;
        }
    }
}

template <class BidirectionalIterator, class Compare>
bool next_permutation (BidirectionalIterator first, BidirectionalIterator last,
                       Compare _RWSTD_COMP)
{
    if (first == last) return false;
    BidirectionalIterator i = first;
    ++i;
    if (i == last) return false;
    i = last;
    --i;

    for (;;)
    {
        BidirectionalIterator ii = i--;
        if (_RWSTD_COMP(*i, *ii))
        {
            BidirectionalIterator j = last;
            while (!_RWSTD_COMP(*i, *--j))
                ;
            iter_swap(i, j);
            reverse(ii, last);
            return true;
        }
        if (i == first)
        {
            reverse(first, last);
            return false;
        }
    }
}

template <class BidirectionalIterator>
bool prev_permutation (BidirectionalIterator first,
                       BidirectionalIterator last)
{
    if (first == last) return false;
    BidirectionalIterator i = first;
    ++i;
    if (i == last) return false;
    i = last;
    --i;

    for (;;)
    {
        BidirectionalIterator ii = i--;
        if (*ii < *i)
        {
            BidirectionalIterator j = last;
            while (!(*--j < *i))
                ;
            iter_swap(i, j);
            reverse(ii, last);
            return true;
        }
        if (i == first)
        {
            reverse(first, last);
            return false;
        }
    }
}

template <class BidirectionalIterator, class Compare>
bool prev_permutation (BidirectionalIterator first, BidirectionalIterator last,
                       Compare _RWSTD_COMP)
{
    if (first == last) return false;
    BidirectionalIterator i = first;
    ++i;
    if (i == last) return false;
    i = last;
    --i;

    for(;;)
    {
        BidirectionalIterator ii = i--;
        if (_RWSTD_COMP(*ii, *i))
        {
            BidirectionalIterator j = last;
            while (!_RWSTD_COMP(*--j, *i))
                ;
            iter_swap(i, j);
            reverse(ii, last);
            return true;
        }
        if (i == first)
        {
            reverse(first, last);
            return false;
        }
    }
}

#ifndef _RWSTD_NO_NAMESPACE
}
#endif

#pragma option pop
#endif /* __ALGORITH_CC */