gcc/libstdc++-v3/include/ext/algorithm
Phil Edwards fc7f0a806c configopts.html, [...]: Tweaks.
2002-07-02  Phil Edwards  <pme@gcc.gnu.org>

	* docs/html/configopts.html, docs/html/install.html:  Tweaks.
	* include/ext/algorithm, include/ext/hash_map, include/ext/hash_set,
	include/ext/iterator, include/ext/numeric, include/ext/rb_tree,
	include/ext/slist, include/ext/stl_rope.h:  Add doxygen hooks.

From-SVN: r55172
2002-07-02 06:17:36 +00:00

537 lines
17 KiB
C++

// Algorithm extensions -*- C++ -*-
// Copyright (C) 2001, 2002 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library 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 2, or (at your option)
// any later version.
// This library 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 this library; see the file COPYING. If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
/*
*
* 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.
*
*
* Copyright (c) 1996
* Silicon Graphics Computer Systems, Inc.
*
* 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. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file ext/algorithm
* This file is a GNU extension to the Standard C++ Library (possibly
* containing extensions from the HP/SGI STL subset). You should only
* include this header if you are using GCC 3 or later.
*/
#ifndef _EXT_ALGORITHM
#define _EXT_ALGORITHM
#pragma GCC system_header
#include <algorithm>
namespace __gnu_cxx
{
using std::ptrdiff_t;
using std::min;
using std::pair;
using std::input_iterator_tag;
using std::random_access_iterator_tag;
using std::iterator_traits;
//--------------------------------------------------
// copy_n (not part of the C++ standard)
template<typename _InputIter, typename _Size, typename _OutputIter>
pair<_InputIter, _OutputIter>
__copy_n(_InputIter __first, _Size __count,
_OutputIter __result,
input_iterator_tag)
{
for ( ; __count > 0; --__count) {
*__result = *__first;
++__first;
++__result;
}
return pair<_InputIter, _OutputIter>(__first, __result);
}
template<typename _RAIter, typename _Size, typename _OutputIter>
inline pair<_RAIter, _OutputIter>
__copy_n(_RAIter __first, _Size __count,
_OutputIter __result,
random_access_iterator_tag)
{
_RAIter __last = __first + __count;
return pair<_RAIter, _OutputIter>(__last,
std::copy(__first, __last, __result));
}
/**
* @brief Copies the range [first,first+count) into [result,result+count).
* @param first An input iterator.
* @param count The number of elements to copy.
* @param result An output iterator.
* @return A std::pair composed of first+count and result+count.
*
* This is an SGI extension.
* This inline function will boil down to a call to @c memmove whenever
* possible. Failing that, if random access iterators are passed, then the
* loop count will be known (and therefore a candidate for compiler
* optimizations such as unrolling).
* @ingroup SGIextensions
*/
template<typename _InputIter, typename _Size, typename _OutputIter>
inline pair<_InputIter, _OutputIter>
copy_n(_InputIter __first, _Size __count, _OutputIter __result)
{
// concept requirements
__glibcpp_function_requires(_InputIteratorConcept<_InputIter>)
__glibcpp_function_requires(_OutputIteratorConcept<_OutputIter,
typename iterator_traits<_InputIter>::value_type>)
return __copy_n(__first, __count, __result,
std::__iterator_category(__first));
}
template<typename _InputIter1, typename _InputIter2>
int
__lexicographical_compare_3way(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2)
{
while (__first1 != __last1 && __first2 != __last2) {
if (*__first1 < *__first2)
return -1;
if (*__first2 < *__first1)
return 1;
++__first1;
++__first2;
}
if (__first2 == __last2) {
return !(__first1 == __last1);
}
else {
return -1;
}
}
inline int
__lexicographical_compare_3way(const unsigned char* __first1,
const unsigned char* __last1,
const unsigned char* __first2,
const unsigned char* __last2)
{
const ptrdiff_t __len1 = __last1 - __first1;
const ptrdiff_t __len2 = __last2 - __first2;
const int __result = std::memcmp(__first1, __first2, min(__len1, __len2));
return __result != 0 ? __result
: (__len1 == __len2 ? 0 : (__len1 < __len2 ? -1 : 1));
}
inline int
__lexicographical_compare_3way(const char* __first1, const char* __last1,
const char* __first2, const char* __last2)
{
#if CHAR_MAX == SCHAR_MAX
return __lexicographical_compare_3way(
(const signed char*) __first1,
(const signed char*) __last1,
(const signed char*) __first2,
(const signed char*) __last2);
#else
return __lexicographical_compare_3way((const unsigned char*) __first1,
(const unsigned char*) __last1,
(const unsigned char*) __first2,
(const unsigned char*) __last2);
#endif
}
/**
* @brief @c memcmp on steroids.
* @param first1 An input iterator.
* @param last1 An input iterator.
* @param first2 An input iterator.
* @param last2 An input iterator.
* @return An int, as with @c memcmp.
*
* The return value will be less than zero if the first range is
* "lexigraphically less than" the second, greater than zero if the second
* range is "lexigraphically less than" the first, and zero otherwise.
* This is an SGI extension.
* @ingroup SGIextensions
*/
template<typename _InputIter1, typename _InputIter2>
int
lexicographical_compare_3way(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2)
{
// concept requirements
__glibcpp_function_requires(_InputIteratorConcept<_InputIter1>)
__glibcpp_function_requires(_InputIteratorConcept<_InputIter2>)
__glibcpp_function_requires(_LessThanComparableConcept<
typename iterator_traits<_InputIter1>::value_type>)
__glibcpp_function_requires(_LessThanComparableConcept<
typename iterator_traits<_InputIter2>::value_type>)
return __lexicographical_compare_3way(__first1, __last1, __first2, __last2);
}
// count and count_if: this version, whose return type is void, was present
// in the HP STL, and is retained as an extension for backward compatibility.
template<typename _InputIter, typename _Tp, typename _Size>
void
count(_InputIter __first, _InputIter __last,
const _Tp& __value,
_Size& __n)
{
// concept requirements
__glibcpp_function_requires(_InputIteratorConcept<_InputIter>)
__glibcpp_function_requires(_EqualityComparableConcept<
typename iterator_traits<_InputIter>::value_type >)
__glibcpp_function_requires(_EqualityComparableConcept<_Tp>)
for ( ; __first != __last; ++__first)
if (*__first == __value)
++__n;
}
template<typename _InputIter, typename _Predicate, typename _Size>
void
count_if(_InputIter __first, _InputIter __last,
_Predicate __pred,
_Size& __n)
{
// concept requirements
__glibcpp_function_requires(_InputIteratorConcept<_InputIter>)
__glibcpp_function_requires(_UnaryPredicateConcept<_Predicate,
typename iterator_traits<_InputIter>::value_type>)
for ( ; __first != __last; ++__first)
if (__pred(*__first))
++__n;
}
// random_sample and random_sample_n (extensions, not part of the standard).
/**
* This is an SGI extension.
* @ingroup SGIextensions
* @doctodo
*/
template<typename _ForwardIter, typename _OutputIter, typename _Distance>
_OutputIter
random_sample_n(_ForwardIter __first, _ForwardIter __last,
_OutputIter __out, const _Distance __n)
{
// concept requirements
__glibcpp_function_requires(_ForwardIteratorConcept<_ForwardIter>)
__glibcpp_function_requires(_OutputIteratorConcept<_OutputIter,
typename iterator_traits<_ForwardIter>::value_type>)
_Distance __remaining = std::distance(__first, __last);
_Distance __m = min(__n, __remaining);
while (__m > 0) {
if (std::__random_number(__remaining) < __m) {
*__out = *__first;
++__out;
--__m;
}
--__remaining;
++__first;
}
return __out;
}
/**
* This is an SGI extension.
* @ingroup SGIextensions
* @doctodo
*/
template<typename _ForwardIter, typename _OutputIter, typename _Distance,
typename _RandomNumberGenerator>
_OutputIter
random_sample_n(_ForwardIter __first, _ForwardIter __last,
_OutputIter __out, const _Distance __n,
_RandomNumberGenerator& __rand)
{
// concept requirements
__glibcpp_function_requires(_ForwardIteratorConcept<_ForwardIter>)
__glibcpp_function_requires(_OutputIteratorConcept<_OutputIter,
typename iterator_traits<_ForwardIter>::value_type>)
__glibcpp_function_requires(_UnaryFunctionConcept<
_RandomNumberGenerator, _Distance, _Distance>)
_Distance __remaining = std::distance(__first, __last);
_Distance __m = min(__n, __remaining);
while (__m > 0) {
if (__rand(__remaining) < __m) {
*__out = *__first;
++__out;
--__m;
}
--__remaining;
++__first;
}
return __out;
}
template<typename _InputIter, typename _RandomAccessIter, typename _Distance>
_RandomAccessIter
__random_sample(_InputIter __first, _InputIter __last,
_RandomAccessIter __out,
const _Distance __n)
{
_Distance __m = 0;
_Distance __t = __n;
for ( ; __first != __last && __m < __n; ++__m, ++__first)
__out[__m] = *__first;
while (__first != __last) {
++__t;
_Distance __M = std::__random_number(__t);
if (__M < __n)
__out[__M] = *__first;
++__first;
}
return __out + __m;
}
template<typename _InputIter, typename _RandomAccessIter,
typename _RandomNumberGenerator, typename _Distance>
_RandomAccessIter
__random_sample(_InputIter __first, _InputIter __last,
_RandomAccessIter __out,
_RandomNumberGenerator& __rand,
const _Distance __n)
{
// concept requirements
__glibcpp_function_requires(_UnaryFunctionConcept<
_RandomNumberGenerator, _Distance, _Distance>)
_Distance __m = 0;
_Distance __t = __n;
for ( ; __first != __last && __m < __n; ++__m, ++__first)
__out[__m] = *__first;
while (__first != __last) {
++__t;
_Distance __M = __rand(__t);
if (__M < __n)
__out[__M] = *__first;
++__first;
}
return __out + __m;
}
/**
* This is an SGI extension.
* @ingroup SGIextensions
* @doctodo
*/
template<typename _InputIter, typename _RandomAccessIter>
inline _RandomAccessIter
random_sample(_InputIter __first, _InputIter __last,
_RandomAccessIter __out_first, _RandomAccessIter __out_last)
{
// concept requirements
__glibcpp_function_requires(_InputIteratorConcept<_InputIter>)
__glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIter>)
return __random_sample(__first, __last,
__out_first, __out_last - __out_first);
}
/**
* This is an SGI extension.
* @ingroup SGIextensions
* @doctodo
*/
template<typename _InputIter, typename _RandomAccessIter,
typename _RandomNumberGenerator>
inline _RandomAccessIter
random_sample(_InputIter __first, _InputIter __last,
_RandomAccessIter __out_first, _RandomAccessIter __out_last,
_RandomNumberGenerator& __rand)
{
// concept requirements
__glibcpp_function_requires(_InputIteratorConcept<_InputIter>)
__glibcpp_function_requires(_Mutable_RandomAccessIteratorConcept<
_RandomAccessIter>)
return __random_sample(__first, __last,
__out_first, __rand,
__out_last - __out_first);
}
// is_heap, a predicate testing whether or not a range is
// a heap. This function is an extension, not part of the C++
// standard.
template<typename _RandomAccessIter, typename _Distance>
bool
__is_heap(_RandomAccessIter __first, _Distance __n)
{
_Distance __parent = 0;
for (_Distance __child = 1; __child < __n; ++__child) {
if (__first[__parent] < __first[__child])
return false;
if ((__child & 1) == 0)
++__parent;
}
return true;
}
template<typename _RandomAccessIter, typename _Distance,
typename _StrictWeakOrdering>
bool
__is_heap(_RandomAccessIter __first, _StrictWeakOrdering __comp,
_Distance __n)
{
_Distance __parent = 0;
for (_Distance __child = 1; __child < __n; ++__child) {
if (__comp(__first[__parent], __first[__child]))
return false;
if ((__child & 1) == 0)
++__parent;
}
return true;
}
/**
* This is an SGI extension.
* @ingroup SGIextensions
* @doctodo
*/
template<typename _RandomAccessIter>
inline bool
is_heap(_RandomAccessIter __first, _RandomAccessIter __last)
{
// concept requirements
__glibcpp_function_requires(_RandomAccessIteratorConcept<_RandomAccessIter>)
__glibcpp_function_requires(_LessThanComparableConcept<
typename iterator_traits<_RandomAccessIter>::value_type>)
return __is_heap(__first, __last - __first);
}
/**
* This is an SGI extension.
* @ingroup SGIextensions
* @doctodo
*/
template<typename _RandomAccessIter, typename _StrictWeakOrdering>
inline bool
is_heap(_RandomAccessIter __first, _RandomAccessIter __last,
_StrictWeakOrdering __comp)
{
// concept requirements
__glibcpp_function_requires(_RandomAccessIteratorConcept<_RandomAccessIter>)
__glibcpp_function_requires(_BinaryPredicateConcept<_StrictWeakOrdering,
typename iterator_traits<_RandomAccessIter>::value_type,
typename iterator_traits<_RandomAccessIter>::value_type>)
return __is_heap(__first, __comp, __last - __first);
}
// is_sorted, a predicated testing whether a range is sorted in
// nondescending order. This is an extension, not part of the C++
// standard.
/**
* This is an SGI extension.
* @ingroup SGIextensions
* @doctodo
*/
template<typename _ForwardIter>
bool
is_sorted(_ForwardIter __first, _ForwardIter __last)
{
// concept requirements
__glibcpp_function_requires(_ForwardIteratorConcept<_ForwardIter>)
__glibcpp_function_requires(_LessThanComparableConcept<
typename iterator_traits<_ForwardIter>::value_type>)
if (__first == __last)
return true;
_ForwardIter __next = __first;
for (++__next; __next != __last; __first = __next, ++__next) {
if (*__next < *__first)
return false;
}
return true;
}
/**
* This is an SGI extension.
* @ingroup SGIextensions
* @doctodo
*/
template<typename _ForwardIter, typename _StrictWeakOrdering>
bool
is_sorted(_ForwardIter __first, _ForwardIter __last, _StrictWeakOrdering __comp)
{
// concept requirements
__glibcpp_function_requires(_ForwardIteratorConcept<_ForwardIter>)
__glibcpp_function_requires(_BinaryPredicateConcept<_StrictWeakOrdering,
typename iterator_traits<_ForwardIter>::value_type,
typename iterator_traits<_ForwardIter>::value_type>)
if (__first == __last)
return true;
_ForwardIter __next = __first;
for (++__next; __next != __last; __first = __next, ++__next) {
if (__comp(*__next, *__first))
return false;
}
return true;
}
} // namespace __gnu_cxx
#endif /* _EXT_ALGORITHM */