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// Bits and pieces used in algorithms -*- C++ -*-
// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
// 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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// 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) 1996-1998
* 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 stl_algobase.h
* This is an internal header file, included by other library headers.
* You should not attempt to use it directly.
*/
#ifndef _ALGOBASE_H
#define _ALGOBASE_H 1
#include <bits/c++config.h>
#include <cstring>
#include <climits>
#include <cstdlib>
#include <cstddef>
#include <iosfwd>
#include <bits/stl_pair.h>
#include <bits/cpp_type_traits.h>
#include <ext/type_traits.h>
#include <bits/stl_iterator_base_types.h>
#include <bits/stl_iterator_base_funcs.h>
#include <bits/stl_iterator.h>
#include <bits/concept_check.h>
#include <debug/debug.h>
_GLIBCXX_BEGIN_NAMESPACE(std)
/**
* @brief Swaps two values.
* @param a A thing of arbitrary type.
* @param b Another thing of arbitrary type.
* @return Nothing.
*
* This is the simple classic generic implementation. It will work on
* any type which has a copy constructor and an assignment operator.
*/
template<typename _Tp>
inline void
swap(_Tp& __a, _Tp& __b)
{
// concept requirements
__glibcxx_function_requires(_SGIAssignableConcept<_Tp>)
_Tp __tmp = __a;
__a = __b;
__b = __tmp;
}
// See http://gcc.gnu.org/ml/libstdc++/2004-08/msg00167.html: in a
// nutshell, we are partially implementing the resolution of DR 187,
// when it's safe, i.e., the value_types are equal.
template<bool _BoolType>
struct __iter_swap
{
template<typename _ForwardIterator1, typename _ForwardIterator2>
static void
iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
{
typedef typename iterator_traits<_ForwardIterator1>::value_type
_ValueType1;
_ValueType1 __tmp = *__a;
*__a = *__b;
*__b = __tmp;
}
};
template<>
struct __iter_swap<true>
{
template<typename _ForwardIterator1, typename _ForwardIterator2>
static void
iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
{
swap(*__a, *__b);
}
};
/**
* @brief Swaps the contents of two iterators.
* @param a An iterator.
* @param b Another iterator.
* @return Nothing.
*
* This function swaps the values pointed to by two iterators, not the
* iterators themselves.
*/
template<typename _ForwardIterator1, typename _ForwardIterator2>
inline void
iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b)
{
typedef typename iterator_traits<_ForwardIterator1>::value_type
_ValueType1;
typedef typename iterator_traits<_ForwardIterator2>::value_type
_ValueType2;
// concept requirements
__glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
_ForwardIterator1>)
__glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
_ForwardIterator2>)
__glibcxx_function_requires(_ConvertibleConcept<_ValueType1,
_ValueType2>)
__glibcxx_function_requires(_ConvertibleConcept<_ValueType2,
_ValueType1>)
typedef typename iterator_traits<_ForwardIterator1>::reference
_ReferenceType1;
typedef typename iterator_traits<_ForwardIterator2>::reference
_ReferenceType2;
std::__iter_swap<__are_same<_ValueType1, _ValueType2>::__value &&
__are_same<_ValueType1 &, _ReferenceType1>::__value &&
__are_same<_ValueType2 &, _ReferenceType2>::__value>::
iter_swap(__a, __b);
}
/**
* @brief This does what you think it does.
* @param a A thing of arbitrary type.
* @param b Another thing of arbitrary type.
* @return The lesser of the parameters.
*
* This is the simple classic generic implementation. It will work on
* temporary expressions, since they are only evaluated once, unlike a
* preprocessor macro.
*/
template<typename _Tp>
inline const _Tp&
min(const _Tp& __a, const _Tp& __b)
{
// concept requirements
__glibcxx_function_requires(_LessThanComparableConcept<_Tp>)
//return __b < __a ? __b : __a;
if (__b < __a)
return __b;
return __a;
}
/**
* @brief This does what you think it does.
* @param a A thing of arbitrary type.
* @param b Another thing of arbitrary type.
* @return The greater of the parameters.
*
* This is the simple classic generic implementation. It will work on
* temporary expressions, since they are only evaluated once, unlike a
* preprocessor macro.
*/
template<typename _Tp>
inline const _Tp&
max(const _Tp& __a, const _Tp& __b)
{
// concept requirements
__glibcxx_function_requires(_LessThanComparableConcept<_Tp>)
//return __a < __b ? __b : __a;
if (__a < __b)
return __b;
return __a;
}
/**
* @brief This does what you think it does.
* @param a A thing of arbitrary type.
* @param b Another thing of arbitrary type.
* @param comp A @link s20_3_3_comparisons comparison functor@endlink.
* @return The lesser of the parameters.
*
* This will work on temporary expressions, since they are only evaluated
* once, unlike a preprocessor macro.
*/
template<typename _Tp, typename _Compare>
inline const _Tp&
min(const _Tp& __a, const _Tp& __b, _Compare __comp)
{
//return __comp(__b, __a) ? __b : __a;
if (__comp(__b, __a))
return __b;
return __a;
}
/**
* @brief This does what you think it does.
* @param a A thing of arbitrary type.
* @param b Another thing of arbitrary type.
* @param comp A @link s20_3_3_comparisons comparison functor@endlink.
* @return The greater of the parameters.
*
* This will work on temporary expressions, since they are only evaluated
* once, unlike a preprocessor macro.
*/
template<typename _Tp, typename _Compare>
inline const _Tp&
max(const _Tp& __a, const _Tp& __b, _Compare __comp)
{
//return __comp(__a, __b) ? __b : __a;
if (__comp(__a, __b))
return __b;
return __a;
}
// All of these auxiliary structs serve two purposes. (1) Replace
// calls to copy with memmove whenever possible. (Memmove, not memcpy,
// because the input and output ranges are permitted to overlap.)
// (2) If we're using random access iterators, then write the loop as
// a for loop with an explicit count.
template<bool, typename>
struct __copy
{
template<typename _II, typename _OI>
static _OI
copy(_II __first, _II __last, _OI __result)
{
for (; __first != __last; ++__result, ++__first)
*__result = *__first;
return __result;
}
};
template<bool _BoolType>
struct __copy<_BoolType, random_access_iterator_tag>
{
template<typename _II, typename _OI>
static _OI
copy(_II __first, _II __last, _OI __result)
{
typedef typename iterator_traits<_II>::difference_type _Distance;
for(_Distance __n = __last - __first; __n > 0; --__n)
{
*__result = *__first;
++__first;
++__result;
}
return __result;
}
};
template<>
struct __copy<true, random_access_iterator_tag>
{
template<typename _Tp>
static _Tp*
copy(const _Tp* __first, const _Tp* __last, _Tp* __result)
{
std::memmove(__result, __first, sizeof(_Tp) * (__last - __first));
return __result + (__last - __first);
}
};
template<typename _II, typename _OI>
inline _OI
__copy_aux(_II __first, _II __last, _OI __result)
{
typedef typename iterator_traits<_II>::value_type _ValueTypeI;
typedef typename iterator_traits<_OI>::value_type _ValueTypeO;
typedef typename iterator_traits<_II>::iterator_category _Category;
const bool __simple = (__is_scalar<_ValueTypeI>::__value
&& __is_pointer<_II>::__value
&& __is_pointer<_OI>::__value
&& __are_same<_ValueTypeI, _ValueTypeO>::__value);
return std::__copy<__simple, _Category>::copy(__first, __last, __result);
}
// Helpers for streambuf iterators (either istream or ostream).
template<typename _CharT>
typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
ostreambuf_iterator<_CharT> >::__type
__copy_aux(_CharT*, _CharT*, ostreambuf_iterator<_CharT>);
template<typename _CharT>
typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
ostreambuf_iterator<_CharT> >::__type
__copy_aux(const _CharT*, const _CharT*, ostreambuf_iterator<_CharT>);
template<typename _CharT>
typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, _CharT*>::__type
__copy_aux(istreambuf_iterator<_CharT>, istreambuf_iterator<_CharT>,
_CharT*);
template<bool, bool>
struct __copy_normal
{
template<typename _II, typename _OI>
static _OI
__copy_n(_II __first, _II __last, _OI __result)
{ return std::__copy_aux(__first, __last, __result); }
};
template<>
struct __copy_normal<true, false>
{
template<typename _II, typename _OI>
static _OI
__copy_n(_II __first, _II __last, _OI __result)
{ return std::__copy_aux(__first.base(), __last.base(), __result); }
};
template<>
struct __copy_normal<false, true>
{
template<typename _II, typename _OI>
static _OI
__copy_n(_II __first, _II __last, _OI __result)
{ return _OI(std::__copy_aux(__first, __last, __result.base())); }
};
template<>
struct __copy_normal<true, true>
{
template<typename _II, typename _OI>
static _OI
__copy_n(_II __first, _II __last, _OI __result)
{ return _OI(std::__copy_aux(__first.base(), __last.base(),
__result.base())); }
};
/**
* @brief Copies the range [first,last) into result.
* @param first An input iterator.
* @param last An input iterator.
* @param result An output iterator.
* @return result + (first - last)
*
* 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). Result may not be contained within
* [first,last); the copy_backward function should be used instead.
*
* Note that the end of the output range is permitted to be contained
* within [first,last).
*/
template<typename _InputIterator, typename _OutputIterator>
inline _OutputIterator
copy(_InputIterator __first, _InputIterator __last,
_OutputIterator __result)
{
// concept requirements
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
__glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator,
typename iterator_traits<_InputIterator>::value_type>)
__glibcxx_requires_valid_range(__first, __last);
const bool __in = __is_normal_iterator<_InputIterator>::__value;
const bool __out = __is_normal_iterator<_OutputIterator>::__value;
return std::__copy_normal<__in, __out>::__copy_n(__first, __last,
__result);
}
// Overload for streambuf iterators.
template<typename _CharT>
typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
ostreambuf_iterator<_CharT> >::__type
copy(istreambuf_iterator<_CharT>, istreambuf_iterator<_CharT>,
ostreambuf_iterator<_CharT>);
template<bool, typename>
struct __copy_backward
{
template<typename _BI1, typename _BI2>
static _BI2
__copy_b(_BI1 __first, _BI1 __last, _BI2 __result)
{
while (__first != __last)
*--__result = *--__last;
return __result;
}
};
template<bool _BoolType>
struct __copy_backward<_BoolType, random_access_iterator_tag>
{
template<typename _BI1, typename _BI2>
static _BI2
__copy_b(_BI1 __first, _BI1 __last, _BI2 __result)
{
typename iterator_traits<_BI1>::difference_type __n;
for (__n = __last - __first; __n > 0; --__n)
*--__result = *--__last;
return __result;
}
};
template<>
struct __copy_backward<true, random_access_iterator_tag>
{
template<typename _Tp>
static _Tp*
__copy_b(const _Tp* __first, const _Tp* __last, _Tp* __result)
{
const ptrdiff_t _Num = __last - __first;
std::memmove(__result - _Num, __first, sizeof(_Tp) * _Num);
return __result - _Num;
}
};
template<typename _BI1, typename _BI2>
inline _BI2
__copy_backward_aux(_BI1 __first, _BI1 __last, _BI2 __result)
{
typedef typename iterator_traits<_BI1>::value_type _ValueType1;
typedef typename iterator_traits<_BI2>::value_type _ValueType2;
typedef typename iterator_traits<_BI1>::iterator_category _Category;
const bool __simple = (__is_scalar<_ValueType1>::__value
&& __is_pointer<_BI1>::__value
&& __is_pointer<_BI2>::__value
&& __are_same<_ValueType1, _ValueType2>::__value);
return std::__copy_backward<__simple, _Category>::__copy_b(__first,
__last,
__result);
}
template<bool, bool>
struct __copy_backward_normal
{
template<typename _BI1, typename _BI2>
static _BI2
__copy_b_n(_BI1 __first, _BI1 __last, _BI2 __result)
{ return std::__copy_backward_aux(__first, __last, __result); }
};
template<>
struct __copy_backward_normal<true, false>
{
template<typename _BI1, typename _BI2>
static _BI2
__copy_b_n(_BI1 __first, _BI1 __last, _BI2 __result)
{ return std::__copy_backward_aux(__first.base(), __last.base(),
__result); }
};
template<>
struct __copy_backward_normal<false, true>
{
template<typename _BI1, typename _BI2>
static _BI2
__copy_b_n(_BI1 __first, _BI1 __last, _BI2 __result)
{ return _BI2(std::__copy_backward_aux(__first, __last,
__result.base())); }
};
template<>
struct __copy_backward_normal<true, true>
{
template<typename _BI1, typename _BI2>
static _BI2
__copy_b_n(_BI1 __first, _BI1 __last, _BI2 __result)
{ return _BI2(std::__copy_backward_aux(__first.base(), __last.base(),
__result.base())); }
};
/**
* @brief Copies the range [first,last) into result.
* @param first A bidirectional iterator.
* @param last A bidirectional iterator.
* @param result A bidirectional iterator.
* @return result - (first - last)
*
* The function has the same effect as copy, but starts at the end of the
* range and works its way to the start, returning the start of the result.
* 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).
*
* Result may not be in the range [first,last). Use copy instead. Note
* that the start of the output range may overlap [first,last).
*/
template <typename _BI1, typename _BI2>
inline _BI2
copy_backward(_BI1 __first, _BI1 __last, _BI2 __result)
{
// concept requirements
__glibcxx_function_requires(_BidirectionalIteratorConcept<_BI1>)
__glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<_BI2>)
__glibcxx_function_requires(_ConvertibleConcept<
typename iterator_traits<_BI1>::value_type,
typename iterator_traits<_BI2>::value_type>)
__glibcxx_requires_valid_range(__first, __last);
const bool __bi1 = __is_normal_iterator<_BI1>::__value;
const bool __bi2 = __is_normal_iterator<_BI2>::__value;
return std::__copy_backward_normal<__bi1, __bi2>::__copy_b_n(__first,
__last,
__result);
}
template<bool>
struct __fill
{
template<typename _ForwardIterator, typename _Tp>
static void
fill(_ForwardIterator __first, _ForwardIterator __last,
const _Tp& __value)
{
for (; __first != __last; ++__first)
*__first = __value;
}
};
template<>
struct __fill<true>
{
template<typename _ForwardIterator, typename _Tp>
static void
fill(_ForwardIterator __first, _ForwardIterator __last,
const _Tp& __value)
{
const _Tp __tmp = __value;
for (; __first != __last; ++__first)
*__first = __tmp;
}
};
/**
* @brief Fills the range [first,last) with copies of value.
* @param first A forward iterator.
* @param last A forward iterator.
* @param value A reference-to-const of arbitrary type.
* @return Nothing.
*
* This function fills a range with copies of the same value. For one-byte
* types filling contiguous areas of memory, this becomes an inline call to
* @c memset.
*/
template<typename _ForwardIterator, typename _Tp>
void
fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value)
{
// concept requirements
__glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
_ForwardIterator>)
__glibcxx_requires_valid_range(__first, __last);
const bool __scalar = __is_scalar<_Tp>::__value;
std::__fill<__scalar>::fill(__first, __last, __value);
}
// Specialization: for one-byte types we can use memset.
inline void
fill(unsigned char* __first, unsigned char* __last, const unsigned char& __c)
{
__glibcxx_requires_valid_range(__first, __last);
const unsigned char __tmp = __c;
std::memset(__first, __tmp, __last - __first);
}
inline void
fill(signed char* __first, signed char* __last, const signed char& __c)
{
__glibcxx_requires_valid_range(__first, __last);
const signed char __tmp = __c;
std::memset(__first, static_cast<unsigned char>(__tmp), __last - __first);
}
inline void
fill(char* __first, char* __last, const char& __c)
{
__glibcxx_requires_valid_range(__first, __last);
const char __tmp = __c;
std::memset(__first, static_cast<unsigned char>(__tmp), __last - __first);
}
template<bool>
struct __fill_n
{
template<typename _OutputIterator, typename _Size, typename _Tp>
static _OutputIterator
fill_n(_OutputIterator __first, _Size __n, const _Tp& __value)
{
for (; __n > 0; --__n, ++__first)
*__first = __value;
return __first;
}
};
template<>
struct __fill_n<true>
{
template<typename _OutputIterator, typename _Size, typename _Tp>
static _OutputIterator
fill_n(_OutputIterator __first, _Size __n, const _Tp& __value)
{
const _Tp __tmp = __value;
for (; __n > 0; --__n, ++__first)
*__first = __tmp;
return __first;
}
};
/**
* @brief Fills the range [first,first+n) with copies of value.
* @param first An output iterator.
* @param n The count of copies to perform.
* @param value A reference-to-const of arbitrary type.
* @return The iterator at first+n.
*
* This function fills a range with copies of the same value. For one-byte
* types filling contiguous areas of memory, this becomes an inline call to
* @c memset.
*/
template<typename _OutputIterator, typename _Size, typename _Tp>
_OutputIterator
fill_n(_OutputIterator __first, _Size __n, const _Tp& __value)
{
// concept requirements
__glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, _Tp>)
const bool __scalar = __is_scalar<_Tp>::__value;
return std::__fill_n<__scalar>::fill_n(__first, __n, __value);
}
template<typename _Size>
inline unsigned char*
fill_n(unsigned char* __first, _Size __n, const unsigned char& __c)
{
std::fill(__first, __first + __n, __c);
return __first + __n;
}
template<typename _Size>
inline signed char*
fill_n(signed char* __first, _Size __n, const signed char& __c)
{
std::fill(__first, __first + __n, __c);
return __first + __n;
}
template<typename _Size>
inline char*
fill_n(char* __first, _Size __n, const char& __c)
{
std::fill(__first, __first + __n, __c);
return __first + __n;
}
/**
* @brief Finds the places in ranges which don't match.
* @param first1 An input iterator.
* @param last1 An input iterator.
* @param first2 An input iterator.
* @return A pair of iterators pointing to the first mismatch.
*
* This compares the elements of two ranges using @c == and returns a pair
* of iterators. The first iterator points into the first range, the
* second iterator points into the second range, and the elements pointed
* to by the iterators are not equal.
*/
template<typename _InputIterator1, typename _InputIterator2>
pair<_InputIterator1, _InputIterator2>
mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
_InputIterator2 __first2)
{
// concept requirements
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
__glibcxx_function_requires(_EqualOpConcept<
typename iterator_traits<_InputIterator1>::value_type,
typename iterator_traits<_InputIterator2>::value_type>)
__glibcxx_requires_valid_range(__first1, __last1);
while (__first1 != __last1 && *__first1 == *__first2)
{
++__first1;
++__first2;
}
return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
}
/**
* @brief Finds the places in ranges which don't match.
* @param first1 An input iterator.
* @param last1 An input iterator.
* @param first2 An input iterator.
* @param binary_pred A binary predicate @link s20_3_1_base functor@endlink.
* @return A pair of iterators pointing to the first mismatch.
*
* This compares the elements of two ranges using the binary_pred
* parameter, and returns a pair
* of iterators. The first iterator points into the first range, the
* second iterator points into the second range, and the elements pointed
* to by the iterators are not equal.
*/
template<typename _InputIterator1, typename _InputIterator2,
typename _BinaryPredicate>
pair<_InputIterator1, _InputIterator2>
mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
_InputIterator2 __first2, _BinaryPredicate __binary_pred)
{
// concept requirements
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
__glibcxx_requires_valid_range(__first1, __last1);
while (__first1 != __last1 && __binary_pred(*__first1, *__first2))
{
++__first1;
++__first2;
}
return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
}
/**
* @brief Tests a range for element-wise equality.
* @param first1 An input iterator.
* @param last1 An input iterator.
* @param first2 An input iterator.
* @return A boolean true or false.
*
* This compares the elements of two ranges using @c == and returns true or
* false depending on whether all of the corresponding elements of the
* ranges are equal.
*/
template<typename _InputIterator1, typename _InputIterator2>
inline bool
equal(_InputIterator1 __first1, _InputIterator1 __last1,
_InputIterator2 __first2)
{
// concept requirements
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
__glibcxx_function_requires(_EqualOpConcept<
typename iterator_traits<_InputIterator1>::value_type,
typename iterator_traits<_InputIterator2>::value_type>)
__glibcxx_requires_valid_range(__first1, __last1);
for (; __first1 != __last1; ++__first1, ++__first2)
if (!(*__first1 == *__first2))
return false;
return true;
}
/**
* @brief Tests a range for element-wise equality.
* @param first1 An input iterator.
* @param last1 An input iterator.
* @param first2 An input iterator.
* @param binary_pred A binary predicate @link s20_3_1_base functor@endlink.
* @return A boolean true or false.
*
* This compares the elements of two ranges using the binary_pred
* parameter, and returns true or
* false depending on whether all of the corresponding elements of the
* ranges are equal.
*/
template<typename _InputIterator1, typename _InputIterator2,
typename _BinaryPredicate>
inline bool
equal(_InputIterator1 __first1, _InputIterator1 __last1,
_InputIterator2 __first2,
_BinaryPredicate __binary_pred)
{
// concept requirements
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
__glibcxx_requires_valid_range(__first1, __last1);
for (; __first1 != __last1; ++__first1, ++__first2)
if (!__binary_pred(*__first1, *__first2))
return false;
return true;
}
/**
* @brief Performs "dictionary" comparison on ranges.
* @param first1 An input iterator.
* @param last1 An input iterator.
* @param first2 An input iterator.
* @param last2 An input iterator.
* @return A boolean true or false.
*
* "Returns true if the sequence of elements defined by the range
* [first1,last1) is lexicographically less than the sequence of elements
* defined by the range [first2,last2). Returns false otherwise."
* (Quoted from [25.3.8]/1.) If the iterators are all character pointers,
* then this is an inline call to @c memcmp.
*/
template<typename _InputIterator1, typename _InputIterator2>
bool
lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
_InputIterator2 __first2, _InputIterator2 __last2)
{
// concept requirements
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
__glibcxx_function_requires(_LessThanOpConcept<
typename iterator_traits<_InputIterator1>::value_type,
typename iterator_traits<_InputIterator2>::value_type>)
__glibcxx_function_requires(_LessThanOpConcept<
typename iterator_traits<_InputIterator2>::value_type,
typename iterator_traits<_InputIterator1>::value_type>)
__glibcxx_requires_valid_range(__first1, __last1);
__glibcxx_requires_valid_range(__first2, __last2);
for (; __first1 != __last1 && __first2 != __last2;
++__first1, ++__first2)
{
if (*__first1 < *__first2)
return true;
if (*__first2 < *__first1)
return false;
}
return __first1 == __last1 && __first2 != __last2;
}
/**
* @brief Performs "dictionary" comparison on ranges.
* @param first1 An input iterator.
* @param last1 An input iterator.
* @param first2 An input iterator.
* @param last2 An input iterator.
* @param comp A @link s20_3_3_comparisons comparison functor@endlink.
* @return A boolean true or false.
*
* The same as the four-parameter @c lexigraphical_compare, but uses the
* comp parameter instead of @c <.
*/
template<typename _InputIterator1, typename _InputIterator2,
typename _Compare>
bool
lexicographical_compare(_InputIterator1 __first1, _InputIterator1 __last1,
_InputIterator2 __first2, _InputIterator2 __last2,
_Compare __comp)
{
// concept requirements
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
__glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
__glibcxx_requires_valid_range(__first1, __last1);
__glibcxx_requires_valid_range(__first2, __last2);
for (; __first1 != __last1 && __first2 != __last2;
++__first1, ++__first2)
{
if (__comp(*__first1, *__first2))
return true;
if (__comp(*__first2, *__first1))
return false;
}
return __first1 == __last1 && __first2 != __last2;
}
inline bool
lexicographical_compare(const unsigned char* __first1,
const unsigned char* __last1,
const unsigned char* __first2,
const unsigned char* __last2)
{
__glibcxx_requires_valid_range(__first1, __last1);
__glibcxx_requires_valid_range(__first2, __last2);
const size_t __len1 = __last1 - __first1;
const size_t __len2 = __last2 - __first2;
const int __result = std::memcmp(__first1, __first2,
std::min(__len1, __len2));
return __result != 0 ? __result < 0 : __len1 < __len2;
}
inline bool
lexicographical_compare(const char* __first1, const char* __last1,
const char* __first2, const char* __last2)
{
__glibcxx_requires_valid_range(__first1, __last1);
__glibcxx_requires_valid_range(__first2, __last2);
#if CHAR_MAX == SCHAR_MAX
return std::lexicographical_compare((const signed char*) __first1,
(const signed char*) __last1,
(const signed char*) __first2,
(const signed char*) __last2);
#else /* CHAR_MAX == SCHAR_MAX */
return std::lexicographical_compare((const unsigned char*) __first1,
(const unsigned char*) __last1,
(const unsigned char*) __first2,
(const unsigned char*) __last2);
#endif /* CHAR_MAX == SCHAR_MAX */
}
_GLIBCXX_END_NAMESPACE
#endif
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