算法（algorithm）
- 算法概观
- 算法分析和复杂度表示O（）
- 质变算法
- 非质变算法
- 数值算法
算法概观
再好的编程技巧，也无法让一个笨拙的算法起死回生，选择了错误的算法，便注定了失败的命运
以有限的步骤，解决逻辑或数学上的问题，这一专门科目我们称为算法（Algorithms）
广义而言，我们所写的每个程序都是一个算法，其中的每个函数也都是一个算法毕竟他们都是用来解决问题或大或小的逻辑问题或数学问题。本节主要探讨的是70余个STL算法
算法分析和复杂度表示O（）
质变算法
所谓“质变算法”，是指运算过程中更改区间内（迭代器所指）的元素内容，如拷贝、呼唤、替换等等
非质变算法
所谓“非质变算法”，是指运算过程中不会更改区间内（迭代器所指）的元素内容，如查找、匹配、计数、比较、寻找极值等等
数值算法
accumulate：累加
template <class _InputIterator, class _Tp>
_Tp accumulate(_InputIterator __first, _InputIterator __last, _Tp __init)
{
__STL_REQUIRES(_InputIterator, _InputIterator);
for ( ; __first != __last; ++__first)
__init = __init + *__first; // 将每个元素累加到初值init上
return __init;
}
template <class _InputIterator, class _Tp, class _BinaryOperation>
_Tp accumulate(_InputIterator __first, _InputIterator __last, _Tp __init,
_BinaryOperation __binary_op)
{
__STL_REQUIRES(_InputIterator, _InputIterator);
for ( ; __first != __last; ++__first)
__init = __binary_op(__init, *__first);
return __init;
}
adjacent_difference：相邻差计算，注意他最后输出的是一个输出迭代器
根据迭代器继承原理，几乎所有的容器的迭代器都是继承自输入迭代器
template <class _InputIterator, class _OutputIterator, class _Tp>
_OutputIterator
__adjacent_difference(_InputIterator __first, _InputIterator __last,
_OutputIterator __result, _Tp*)
{
_Tp __value = *__first;
while (++__first != __last) {
_Tp __tmp = *__first;
*++__result = __tmp - __value;
__value = __tmp;
}
return ++__result;
}
template <class _InputIterator, class _OutputIterator>
_OutputIterator
adjacent_difference(_InputIterator __first,
_InputIterator __last, _OutputIterator __result)
{
__STL_REQUIRES(_InputIterator, _InputIterator);
__STL_REQUIRES(_OutputIterator, _OutputIterator);
if (__first == __last) return __result;
*__result = *__first;
return __adjacent_difference(__first, __last, __result,
__VALUE_TYPE(__first));
}
template <class _InputIterator, class _OutputIterator, class _Tp,
class _BinaryOperation>
_OutputIterator
__adjacent_difference(_InputIterator __first, _InputIterator __last,
_OutputIterator __result, _Tp*,
_BinaryOperation __binary_op) {
_Tp __value = *__first;
while (++__first != __last) {
_Tp __tmp = *__first;
*++__result = __binary_op(__tmp, __value);
__value = __tmp;
}
return ++__result;
}
template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
_OutputIterator
adjacent_difference(_InputIterator __first, _InputIterator __last,
_OutputIterator __result, _BinaryOperation __binary_op)
{
__STL_REQUIRES(_InputIterator, _InputIterator);
__STL_REQUIRES(_OutputIterator, _OutputIterator);
if (__first == __last) return __result;
*__result = *__first;
return __adjacent_difference(__first, __last, __result,
__VALUE_TYPE(__first),
__binary_op);
}
inner_product：计算内积
template <class _InputIterator1, class _InputIterator2, class _Tp>
_Tp inner_product(_InputIterator1 __first1, _InputIterator1 __last1,
_InputIterator2 __first2, _Tp __init)
{
__STL_REQUIRES(_InputIterator2, _InputIterator);
__STL_REQUIRES(_InputIterator2, _InputIterator);
for ( ; __first1 != __last1; ++__first1, ++__first2)
__init = __init + (*__first1 * *__first2);
return __init;
}
template <class _InputIterator1, class _InputIterator2, class _Tp,
class _BinaryOperation1, class _BinaryOperation2>
_Tp inner_product(_InputIterator1 __first1, _InputIterator1 __last1,
_InputIterator2 __first2, _Tp __init,
_BinaryOperation1 __binary_op1,
_BinaryOperation2 __binary_op2)
{
__STL_REQUIRES(_InputIterator2, _InputIterator);
__STL_REQUIRES(_InputIterator2, _InputIterator);
for ( ; __first1 != __last1; ++__first1, ++__first2)
__init = __binary_op1(__init, __binary_op2(*__first1, *__first2));
return __init;
}
partial_sum：计算局部总和
template <class _InputIterator, class _OutputIterator, class _Tp>
_OutputIterator
__partial_sum(_InputIterator __first, _InputIterator __last,
_OutputIterator __result, _Tp*)
{
_Tp __value = *__first;
while (++__first != __last) {
__value = __value + *__first;
*++__result = __value;
}
return ++__result;
}
template <class _InputIterator, class _OutputIterator>
_OutputIterator
partial_sum(_InputIterator __first, _InputIterator __last,
_OutputIterator __result)
{
__STL_REQUIRES(_InputIterator, _InputIterator);
__STL_REQUIRES(_OutputIterator, _OutputIterator);
if (__first == __last) return __result;
*__result = *__first;
return __partial_sum(__first, __last, __result, __VALUE_TYPE(__first));
}
template <class _InputIterator, class _OutputIterator, class _Tp,
class _BinaryOperation>
_OutputIterator
__partial_sum(_InputIterator __first, _InputIterator __last,
_OutputIterator __result, _Tp*, _BinaryOperation __binary_op)
{
_Tp __value = *__first;
while (++__first != __last) {
__value = __binary_op(__value, *__first);
*++__result = __value;
}
return ++__result;
}
template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
_OutputIterator
partial_sum(_InputIterator __first, _InputIterator __last,
_OutputIterator __result, _BinaryOperation __binary_op)
{
__STL_REQUIRES(_InputIterator, _InputIterator);
__STL_REQUIRES(_OutputIterator, _OutputIterator);
if (__first == __last) return __result;
*__result = *__first;
return __partial_sum(__first, __last, __result, __VALUE_TYPE(__first),
__binary_op);
}
power：计算某数的n幂次方（不在STL中），在SGI专属
template <class _Tp, class _Integer, class _MonoidOperation>
_Tp __power(_Tp __x, _Integer __n, _MonoidOperation __opr)
{
if (__n == 0)
return identity_element(__opr);
else {
while ((__n & 1) == 0) {
__n >>= 1;
__x = __opr(__x, __x);
}
_Tp __result = __x;
__n >>= 1;
while (__n != 0) {
__x = __opr(__x, __x);
if ((__n & 1) != 0)
__result = __opr(__result, __x);
__n >>= 1;
}
return __result;
}
}
template <class _Tp, class _Integer>
inline _Tp __power(_Tp __x, _Integer __n)
{
return __power(__x, __n, multiplies<_Tp>());
}
// Alias for the internal name __power. Note that power is an extension,
// not part of the C++ standard.
template <class _Tp, class _Integer, class _MonoidOperation>
inline _Tp power(_Tp __x, _Integer __n, _MonoidOperation __opr)
{
return __power(__x, __n, __opr);
}
template <class _Tp, class _Integer>
inline _Tp power(_Tp __x, _Integer __n)
{
return __power(__x, __n);
}
iota：设定某个区间的内容，使其内的每个元素从指定的value值开始，呈现递增状态（不在STL中），在SGI专属
template <class _ForwardIter, class _Tp>
void
iota(_ForwardIter __first, _ForwardIter __last, _Tp __value)
{
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
__STL_CONVERTIBLE(_Tp, typename iterator_traits<_ForwardIter>::value_type);
while (__first != __last)
*__first++ = __value++;
}
基本算法
STL并没有区分基本算法和复杂算法，然而SGI却把一些常用的算法定义于<stl_algobase.h>之中，其他算法定义于<stl_algo.h>中
equal：如果两个序列在[first，last）区间内相等，equal（）返回true
template <class _InputIter1, class _InputIter2>
inline bool equal(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_EqualityComparable);
__STL_REQUIRES(typename iterator_traits<_InputIter2>::value_type,
_EqualityComparable);
for ( ; __first1 != __last1; ++__first1, ++__first2)
if (*__first1 != *__first2)
return false;
return true;
}
template <class _InputIter1, class _InputIter2, class _BinaryPredicate>
inline bool equal(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _BinaryPredicate __binary_pred) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
for ( ; __first1 != __last1; ++__first1, ++__first2)
if (!__binary_pred(*__first1, *__first2))
return false;
return true;
}
fill：将[first，last）内的所有元素改填新值（填一样的值value）
template <class _ForwardIter, class _Tp>
void fill(_ForwardIter __first, _ForwardIter __last, const _Tp& __value) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
for ( ; __first != __last; ++__first)
*__first = __value;
}
// Specialization: for one-byte types we can use memset.
inline void fill(unsigned char* __first, unsigned char* __last,
const unsigned char& __c) {
unsigned char __tmp = __c;
memset(__first, __tmp, __last - __first);
}
inline void fill(signed char* __first, signed char* __last,
const signed char& __c) {
signed char __tmp = __c;
memset(__first, static_cast<unsigned char>(__tmp), __last - __first);
}
inline void fill(char* __first, char* __last, const char& __c) {
char __tmp = __c;
memset(__first, static_cast<unsigned char>(__tmp), __last - __first);
}
fill_n：将[first，last）内的前n个元素改填新值，返回的迭代器指向被填入的最后一个元素的下一个位置
template <class _OutputIter, class _Size, class _Tp>
_OutputIter fill_n(_OutputIter __first, _Size __n, const _Tp& __value) {
__STL_REQUIRES(_OutputIter, _OutputIterator);
for ( ; __n > 0; --__n, ++__first)
*__first = __value;
return __first;
}
iter_swap：将两个Fowarditerators所指的对象对调
template <class _ForwardIter1, class _ForwardIter2, class _Tp>
inline void __iter_swap(_ForwardIter1 __a, _ForwardIter2 __b, _Tp*) {
_Tp __tmp = *__a;
*__a = *__b;
*__b = __tmp;
}
template <class _ForwardIter1, class _ForwardIter2>
inline void iter_swap(_ForwardIter1 __a, _ForwardIter2 __b) {
__STL_REQUIRES(_ForwardIter1, _Mutable_ForwardIterator);
__STL_REQUIRES(_ForwardIter2, _Mutable_ForwardIterator);
__STL_CONVERTIBLE(typename iterator_traits<_ForwardIter1>::value_type,
typename iterator_traits<_ForwardIter2>::value_type);
__STL_CONVERTIBLE(typename iterator_traits<_ForwardIter2>::value_type,
typename iterator_traits<_ForwardIter1>::value_type);
__iter_swap(__a, __b, __VALUE_TYPE(__a));
}
lexicographical_compare：
template <class _InputIter1, class _InputIter2>
bool lexicographical_compare(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_LessThanComparable);
__STL_REQUIRES(typename iterator_traits<_InputIter2>::value_type,
_LessThanComparable);
for ( ; __first1 != __last1 && __first2 != __last2
; ++__first1, ++__first2) {
if (*__first1 < *__first2)
return true;
if (*__first2 < *__first1)
return false;
}
return __first1 == __last1 && __first2 != __last2;
}
template <class _InputIter1, class _InputIter2, class _Compare>
bool lexicographical_compare(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_Compare __comp) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
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)
{
const size_t __len1 = __last1 - __first1;
const size_t __len2 = __last2 - __first2;
const int __result = memcmp(__first1, __first2, 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)
{
#if CHAR_MAX == SCHAR_MAX
return lexicographical_compare((const signed char*) __first1,
(const signed char*) __last1,
(const signed char*) __first2,
(const signed char*) __last2);
#else /* CHAR_MAX == SCHAR_MAX */
return lexicographical_compare((const unsigned char*) __first1,
(const unsigned char*) __last1,
(const unsigned char*) __first2,
(const unsigned char*) __last2);
#endif /* CHAR_MAX == SCHAR_MAX */
}
template <class _InputIter1, class _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 = 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
}
template <class _InputIter1, class _InputIter2>
int lexicographical_compare_3way(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2)
{
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_LessThanComparable);
__STL_REQUIRES(typename iterator_traits<_InputIter2>::value_type,
_LessThanComparable);
return __lexicographical_compare_3way(__first1, __last1, __first2, __last2);
}
min：求最小值
template <class _Tp>
inline const _Tp& min(const _Tp& __a, const _Tp& __b) {
__STL_REQUIRES(_Tp, _LessThanComparable);
return __b < __a ? __b : __a;
}
template <class _Tp, class _Compare>
inline const _Tp& min(const _Tp& __a, const _Tp& __b, _Compare __comp) {
return __comp(__b, __a) ? __b : __a;
}
max：求最大值
template <class _Tp>
inline const _Tp& max(const _Tp& __a, const _Tp& __b) {
__STL_REQUIRES(_Tp, _LessThanComparable);
return __a < __b ? __b : __a;
}
template <class _Tp, class _Compare>
inline const _Tp& max(const _Tp& __a, const _Tp& __b, _Compare __comp) {
return __comp(__a, __b) ? __b : __a;
}
mismatch：用平行比较两个序列，指出两者之间的第一个不匹配点，返回一对迭代器
template <class _InputIter1, class _InputIter2>
pair<_InputIter1, _InputIter2> mismatch(_InputIter1 __first1,
_InputIter1 __last1,
_InputIter2 __first2) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_EqualityComparable);
__STL_REQUIRES(typename iterator_traits<_InputIter2>::value_type,
_EqualityComparable);
while (__first1 != __last1 && *__first1 == *__first2) {
++__first1;
++__first2;
}
return pair<_InputIter1, _InputIter2>(__first1, __first2);
}
template <class _InputIter1, class _InputIter2, class _BinaryPredicate>
pair<_InputIter1, _InputIter2> mismatch(_InputIter1 __first1,
_InputIter1 __last1,
_InputIter2 __first2,
_BinaryPredicate __binary_pred) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
while (__first1 != __last1 && __binary_pred(*__first1, *__first2)) {
++__first1;
++__first2;
}
return pair<_InputIter1, _InputIter2>(__first1, __first2);
}
swap：交换两个对象的内容
template <class _ForwardIter1, class _ForwardIter2, class _Tp>
inline void __iter_swap(_ForwardIter1 __a, _ForwardIter2 __b, _Tp*) {
_Tp __tmp = *__a;
*__a = *__b;
*__b = __tmp;
}
template <class _ForwardIter1, class _ForwardIter2>
inline void iter_swap(_ForwardIter1 __a, _ForwardIter2 __b) {
__STL_REQUIRES(_ForwardIter1, _Mutable_ForwardIterator);
__STL_REQUIRES(_ForwardIter2, _Mutable_ForwardIterator);
__STL_CONVERTIBLE(typename iterator_traits<_ForwardIter1>::value_type,
typename iterator_traits<_ForwardIter2>::value_type);
__STL_CONVERTIBLE(typename iterator_traits<_ForwardIter2>::value_type,
typename iterator_traits<_ForwardIter1>::value_type);
__iter_swap(__a, __b, __VALUE_TYPE(__a));
}
template <class _Tp>
inline void swap(_Tp& __a, _Tp& __b) {
__STL_REQUIRES(_Tp, _Assignable);
_Tp __tmp = __a;
__a = __b;
__b = __tmp;
}
copy：将区间[first，last）内的元素复制到输出区间[result，result+（last-first））内。
template <class _InputIter, class _OutputIter, class _Distance>
inline _OutputIter __copy(_InputIter __first, _InputIter __last,
_OutputIter __result,
input_iterator_tag, _Distance*)
{
for ( ; __first != __last; ++__result, ++__first)
*__result = *__first;
return __result;
}
template <class _InputIter, class _OutputIter>
inline _OutputIter copy(_InputIter __first, _InputIter __last,
_OutputIter __result)
{
return __copy(__first, __last, __result,
__ITERATOR_CATEGORY(__first),
__DISTANCE_TYPE(__first));
}
template <class _InputIter, class _OutputIter, class _Distance>
inline _OutputIter __copy(_InputIter __first, _InputIter __last,
_OutputIter __result,
input_iterator_tag, _Distance*)
{
for ( ; __first != __last; ++__result, ++__first)
*__result = *__first;
return __result;
}
template <class _RandomAccessIter, class _OutputIter, class _Distance>
inline _OutputIter
__copy(_RandomAccessIter __first, _RandomAccessIter __last,
_OutputIter __result, random_access_iterator_tag, _Distance*)
{
for (_Distance __n = __last - __first; __n > 0; --__n) {
*__result = *__first;
++__first;
++__result;
}
return __result;
}
copy_backward：将[first，last）区间内的内容，以逆行的方式复制到以result-1为起点，方向亦为逆行的起点
template <class _BidirectionalIter1, class _BidirectionalIter2,
class _Distance>
inline _BidirectionalIter2 __copy_backward(_BidirectionalIter1 __first,
_BidirectionalIter1 __last,
_BidirectionalIter2 __result,
bidirectional_iterator_tag,
_Distance*)
{
while (__first != __last)
*--__result = *--__last;
return __result;
}
template <class _RandomAccessIter, class _BidirectionalIter, class _Distance>
inline _BidirectionalIter __copy_backward(_RandomAccessIter __first,
_RandomAccessIter __last,
_BidirectionalIter __result,
random_access_iterator_tag,
_Distance*)
{
for (_Distance __n = __last - __first; __n > 0; --__n)
*--__result = *--__last;
return __result;
}
template <class _BI1, class _BI2>
inline _BI2 copy_backward(_BI1 __first, _BI1 __last, _BI2 __result) {
return __copy_backward(__first, __last, __result,
__ITERATOR_CATEGORY(__first),
__DISTANCE_TYPE(__first));
}
Set相关算法
在<stl_algo.h>中，应用于有序区间
set_union：取并集
template <class _InputIter1, class _InputIter2, class _OutputIter>
_OutputIter set_union(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_LessThanComparable);
while (__first1 != __last1 && __first2 != __last2) {
if (*__first1 < *__first2) {
*__result = *__first1;
++__first1;
}
else if (*__first2 < *__first1) {
*__result = *__first2;
++__first2;
}
else {
*__result = *__first1;
++__first1;
++__first2;
}
++__result;
}
return copy(__first2, __last2, copy(__first1, __last1, __result));
}
template <class _InputIter1, class _InputIter2, class _OutputIter,
class _Compare>
_OutputIter set_union(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result, _Compare __comp) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
while (__first1 != __last1 && __first2 != __last2) {
if (__comp(*__first1, *__first2)) {
*__result = *__first1;
++__first1;
}
else if (__comp(*__first2, *__first1)) {
*__result = *__first2;
++__first2;
}
else {
*__result = *__first1;
++__first1;
++__first2;
}
++__result;
}
return copy(__first2, __last2, copy(__first1, __last1, __result));
}
set_intersection：取交集
template <class _InputIter1, class _InputIter2, class _OutputIter>
_OutputIter set_intersection(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_LessThanComparable);
while (__first1 != __last1 && __first2 != __last2)
if (*__first1 < *__first2)
++__first1;
else if (*__first2 < *__first1)
++__first2;
else {
*__result = *__first1;
++__first1;
++__first2;
++__result;
}
return __result;
}
template <class _InputIter1, class _InputIter2, class _OutputIter,
class _Compare>
_OutputIter set_intersection(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result, _Compare __comp) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
while (__first1 != __last1 && __first2 != __last2)
if (__comp(*__first1, *__first2))
++__first1;
else if (__comp(*__first2, *__first1))
++__first2;
else {
*__result = *__first1;
++__first1;
++__first2;
++__result;
}
return __result;
}
set_difference：取差集
template <class _InputIter1, class _InputIter2, class _OutputIter>
_OutputIter set_difference(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_LessThanComparable);
while (__first1 != __last1 && __first2 != __last2)
if (*__first1 < *__first2) {
*__result = *__first1;
++__first1;
++__result;
}
else if (*__first2 < *__first1)
++__first2;
else {
++__first1;
++__first2;
}
return copy(__first1, __last1, __result);
}
template <class _InputIter1, class _InputIter2, class _OutputIter,
class _Compare>
_OutputIter set_difference(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result, _Compare __comp) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
while (__first1 != __last1 && __first2 != __last2)
if (__comp(*__first1, *__first2)) {
*__result = *__first1;
++__first1;
++__result;
}
else if (__comp(*__first2, *__first1))
++__first2;
else {
++__first1;
++__first2;
}
return copy(__first1, __last1, __result);
}
set_symmetric_difference：对称差集：（s1-s2）∪（s2-s1）
template <class _InputIter1, class _InputIter2, class _OutputIter>
_OutputIter
set_symmetric_difference(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_LessThanComparable);
while (__first1 != __last1 && __first2 != __last2)
if (*__first1 < *__first2) {
*__result = *__first1;
++__first1;
++__result;
}
else if (*__first2 < *__first1) {
*__result = *__first2;
++__first2;
++__result;
}
else {
++__first1;
++__first2;
}
return copy(__first2, __last2, copy(__first1, __last1, __result));
}
template <class _InputIter1, class _InputIter2, class _OutputIter,
class _Compare>
_OutputIter
set_symmetric_difference(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result,
_Compare __comp) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
while (__first1 != __last1 && __first2 != __last2)
if (__comp(*__first1, *__first2)) {
*__result = *__first1;
++__first1;
++__result;
}
else if (__comp(*__first2, *__first1)) {
*__result = *__first2;
++__first2;
++__result;
}
else {
++__first1;
++__first2;
}
return copy(__first2, __last2, copy(__first1, __last1, __result));
}
heap算法
其他算法
单纯的数据处理
adjacent_find：找出第一组满足条件的相邻元素
template <class _ForwardIter>
_ForwardIter adjacent_find(_ForwardIter __first, _ForwardIter __last) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES(typename iterator_traits<_ForwardIter>::value_type,
_EqualityComparable);
if (__first == __last)
return __last;
_ForwardIter __next = __first;
while(++__next != __last) {
if (*__first == *__next)
return __first;
__first = __next;
}
return __last;
}
template <class _ForwardIter, class _BinaryPredicate>
_ForwardIter adjacent_find(_ForwardIter __first, _ForwardIter __last,
_BinaryPredicate __binary_pred) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_BINARY_FUNCTION_CHECK(_BinaryPredicate, bool,
typename iterator_traits<_ForwardIter>::value_type,
typename iterator_traits<_ForwardIter>::value_type);
if (__first == __last)
return __last;
_ForwardIter __next = __first;
while(++__next != __last) {
if (__binary_pred(*__first, *__next))
return __first;
__first = __next;
}
return __last;
}
count：运用equality运算符，将区间[first，last）区间内的每一个元素拿来和指定值value做比较，并返回与value相等的元素个数
template <class _InputIter, class _Tp, class _Size>
void count(_InputIter __first, _InputIter __last, const _Tp& __value,
_Size& __n) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(typename iterator_traits<_InputIter>::value_type,
_EqualityComparable);
__STL_REQUIRES(_Tp, _EqualityComparable);
for ( ; __first != __last; ++__first)
if (*__first == __value)
++__n;
}
count_if：将指定操作（一个仿函数）pred实施于[first，last）区间内的每一个元素身上，并将“造成pred之计算结果为true”的所有元素的个数返回
template <class _InputIter, class _Predicate, class _Size>
void count_if(_InputIter __first, _InputIter __last, _Predicate __pred,
_Size& __n) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_UNARY_FUNCTION_CHECK(_Predicate, bool,
typename iterator_traits<_InputIter>::value_type);
for ( ; __first != __last; ++__first)
if (__pred(*__first))
++__n;
}
find：运用equality运算符，循环查找区间[first，last）区间内的所有元素，找出第一个匹配“等同条件”，找到，返回一个迭代器，否则返回迭代器last
template <class _InputIter, class _Tp>
inline _InputIter find(_InputIter __first, _InputIter __last,
const _Tp& __val)
{
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES_BINARY_OP(_OP_EQUAL, bool,
typename iterator_traits<_InputIter>::value_type, _Tp);
return find(__first, __last, __val, __ITERATOR_CATEGORY(__first));
}
template <class _InputIter, class _Tp>
inline _InputIter find(_InputIter __first, _InputIter __last,
const _Tp& __val,
input_iterator_tag)
{
while (__first != __last && !(*__first == __val))
++__first;
return __first;
}
find_if：根据指定的pred运算条件（以仿函数表示），循环查找[first，last）内的所有元素，找出第一个令pred运算结果为true者
template <class _InputIter, class _Predicate>
inline _InputIter find_if(_InputIter __first, _InputIter __last,
_Predicate __pred,
input_iterator_tag)
{
while (__first != __last && !__pred(*__first))
++__first;
return __first;
}
find_end：在序列一[first1，last1）所涵盖的区间中，查找序列二[first2，last2）的最后一次出现点，如果不存在，返回迭代器last1
template <class _ForwardIter1, class _ForwardIter2>
_ForwardIter1 __find_end(_ForwardIter1 __first1, _ForwardIter1 __last1,
_ForwardIter2 __first2, _ForwardIter2 __last2,
forward_iterator_tag, forward_iterator_tag)
{
if (__first2 == __last2)
return __last1;
else {
_ForwardIter1 __result = __last1;
while (1) {
_ForwardIter1 __new_result
= search(__first1, __last1, __first2, __last2);
if (__new_result == __last1)
return __result;
else {
__result = __new_result;
__first1 = __new_result;
++__first1;
}
}
}
}
template <class _ForwardIter1, class _ForwardIter2,
class _BinaryPredicate>
_ForwardIter1 __find_end(_ForwardIter1 __first1, _ForwardIter1 __last1,
_ForwardIter2 __first2, _ForwardIter2 __last2,
forward_iterator_tag, forward_iterator_tag,
_BinaryPredicate __comp)
{
if (__first2 == __last2)
return __last1;
else {
_ForwardIter1 __result = __last1;
while (1) {
_ForwardIter1 __new_result
= search(__first1, __last1, __first2, __last2, __comp);
if (__new_result == __last1)
return __result;
else {
__result = __new_result;
__first1 = __new_result;
++__first1;
}
}
}
}
template <class _ForwardIter1, class _ForwardIter2>
inline _ForwardIter1
find_end(_ForwardIter1 __first1, _ForwardIter1 __last1,
_ForwardIter2 __first2, _ForwardIter2 __last2)
{
__STL_REQUIRES(_ForwardIter1, _ForwardIterator);
__STL_REQUIRES(_ForwardIter2, _ForwardIterator);
__STL_REQUIRES_BINARY_OP(_OP_EQUAL, bool,
typename iterator_traits<_ForwardIter1>::value_type,
typename iterator_traits<_ForwardIter2>::value_type);
return __find_end(__first1, __last1, __first2, __last2,
__ITERATOR_CATEGORY(__first1),
__ITERATOR_CATEGORY(__first2));
}
template <class _ForwardIter1, class _ForwardIter2,
class _BinaryPredicate>
inline _ForwardIter1
find_end(_ForwardIter1 __first1, _ForwardIter1 __last1,
_ForwardIter2 __first2, _ForwardIter2 __last2,
_BinaryPredicate __comp)
{
__STL_REQUIRES(_ForwardIter1, _ForwardIterator);
__STL_REQUIRES(_ForwardIter2, _ForwardIterator);
__STL_BINARY_FUNCTION_CHECK(_BinaryPredicate, bool,
typename iterator_traits<_ForwardIter1>::value_type,
typename iterator_traits<_ForwardIter2>::value_type);
return __find_end(__first1, __last1, __first2, __last2,
__ITERATOR_CATEGORY(__first1),
__ITERATOR_CATEGORY(__first2),
__comp);
}
find_first_if：在序列一[first1，last1）所涵盖的区间中，查找序列二[first2，last2）的第一次出现
template <class _InputIter, class _ForwardIter>
_InputIter find_first_of(_InputIter __first1, _InputIter __last1,
_ForwardIter __first2, _ForwardIter __last2)
{
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES_BINARY_OP(_OP_EQUAL, bool,
typename iterator_traits<_InputIter>::value_type,
typename iterator_traits<_ForwardIter>::value_type);
for ( ; __first1 != __last1; ++__first1)
for (_ForwardIter __iter = __first2; __iter != __last2; ++__iter)
if (*__first1 == *__iter)
return __first1;
return __last1;
}
template <class _InputIter, class _ForwardIter, class _BinaryPredicate>
_InputIter find_first_of(_InputIter __first1, _InputIter __last1,
_ForwardIter __first2, _ForwardIter __last2,
_BinaryPredicate __comp)
{
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_BINARY_FUNCTION_CHECK(_BinaryPredicate, bool,
typename iterator_traits<_InputIter>::value_type,
typename iterator_traits<_ForwardIter>::value_type);
for ( ; __first1 != __last1; ++__first1)
for (_ForwardIter __iter = __first2; __iter != __last2; ++__iter)
if (__comp(*__first1, *__iter))
return __first1;
return __last1;
}
generate：将仿函数的运算结果填写在[first，last）区间的所有元素上
template <class _ForwardIter, class _Generator>
void generate(_ForwardIter __first, _ForwardIter __last, _Generator __gen) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_GENERATOR_CHECK(_Generator,
typename iterator_traits<_ForwardIter>::value_type);
for ( ; __first != __last; ++__first)
*__first = __gen();
}
generate_n：将仿函数gen的运算结果填写在从迭代器first开始的第n个元素身上
template <class _OutputIter, class _Size, class _Generator>
_OutputIter generate_n(_OutputIter __first, _Size __n, _Generator __gen) {
__STL_REQUIRES(_OutputIter, _OutputIterator);
for ( ; __n > 0; --__n, ++__first)
*__first = __gen();
return __first;
}
includes：应用于有序区间，判断序列二是否“涵盖于”序列一
template <class _InputIter1, class _InputIter2>
bool includes(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_LessThanComparable);
while (__first1 != __last1 && __first2 != __last2)
if (*__first2 < *__first1)
return false;
else if(*__first1 < *__first2)
++__first1;
else
++__first1, ++__first2;
return __first2 == __last2;
}
template <class _InputIter1, class _InputIter2, class _Compare>
bool includes(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2, _Compare __comp) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
while (__first1 != __last1 && __first2 != __last2)
if (__comp(*__first2, *__first1))
return false;
else if(__comp(*__first1, *__first2))
++__first1;
else
++__first1, ++__first2;
return __first2 == __last2;
}
merge：应用于有序区间，将两个经过排序的集合S1和S2，合并起来置于另一段空间
template <class _InputIter1, class _InputIter2, class _OutputIter>
_OutputIter merge(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_REQUIRES(typename iterator_traits<_InputIter1>::value_type,
_LessThanComparable);
while (__first1 != __last1 && __first2 != __last2) {
if (*__first2 < *__first1) {
*__result = *__first2;
++__first2;
}
else {
*__result = *__first1;
++__first1;
}
++__result;
}
return copy(__first2, __last2, copy(__first1, __last1, __result));
}
template <class _InputIter1, class _InputIter2, class _OutputIter,
class _Compare>
_OutputIter merge(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _InputIter2 __last2,
_OutputIter __result, _Compare __comp) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES_SAME_TYPE(
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter2>::value_type);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_InputIter1>::value_type,
typename iterator_traits<_InputIter1>::value_type);
while (__first1 != __last1 && __first2 != __last2) {
if (__comp(*__first2, *__first1)) {
*__result = *__first2;
++__first2;
}
else {
*__result = *__first1;
++__first1;
}
++__result;
}
return copy(__first2, __last2, copy(__first1, __last1, __result));
}
min_element：返回一个迭代器，指向序列中数值最小的元素
template <class _ForwardIter>
_ForwardIter min_element(_ForwardIter __first, _ForwardIter __last) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES(typename iterator_traits<_ForwardIter>::value_type,
_LessThanComparable);
if (__first == __last) return __first;
_ForwardIter __result = __first;
while (++__first != __last)
if (*__first < *__result)
__result = __first;
return __result;
}
template <class _ForwardIter, class _Compare>
_ForwardIter min_element(_ForwardIter __first, _ForwardIter __last,
_Compare __comp) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_ForwardIter>::value_type,
typename iterator_traits<_ForwardIter>::value_type);
if (__first == __last) return __first;
_ForwardIter __result = __first;
while (++__first != __last)
if (__comp(*__first, *__result))
__result = __first;
return __result;
}
max_element：返回一个迭代器，指向序列中数值最大的元素
template <class _ForwardIter>
_ForwardIter max_element(_ForwardIter __first, _ForwardIter __last) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES(typename iterator_traits<_ForwardIter>::value_type,
_LessThanComparable);
if (__first == __last) return __first;
_ForwardIter __result = __first;
while (++__first != __last)
if (*__result < *__first)
__result = __first;
return __result;
}
template <class _ForwardIter, class _Compare>
_ForwardIter max_element(_ForwardIter __first, _ForwardIter __last,
_Compare __comp) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_ForwardIter>::value_type,
typename iterator_traits<_ForwardIter>::value_type);
if (__first == __last) return __first;
_ForwardIter __result = __first;
while (++__first != __last)
if (__comp(*__result, *__first)) __result = __first;
return __result;
}
partition：将区间[first，last）中的元素重新排列，所有被一元条件运算pred判定为true的元素，都会被放在区间的前段，被判定为false的元素，都会被放在区间的后段
template <class _ForwardIter, class _Predicate>
inline _ForwardIter partition(_ForwardIter __first,
_ForwardIter __last,
_Predicate __pred) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
__STL_UNARY_FUNCTION_CHECK(_Predicate, bool,
typename iterator_traits<_ForwardIter>::value_type);
return __partition(__first, __last, __pred, __ITERATOR_CATEGORY(__first));
}
template <class _ForwardIter, class _Predicate>
_ForwardIter __partition(_ForwardIter __first,
_ForwardIter __last,
_Predicate __pred,
forward_iterator_tag) {
if (__first == __last) return __first;
while (__pred(*__first))
if (++__first == __last) return __first;
_ForwardIter __next = __first;
while (++__next != __last)
if (__pred(*__next)) {
swap(*__first, *__next);
++__first;
}
return __first;
}
template <class _BidirectionalIter, class _Predicate>
_BidirectionalIter __partition(_BidirectionalIter __first,
_BidirectionalIter __last,
_Predicate __pred,
bidirectional_iterator_tag) {
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;
}
}
remove：移除（但不删除），将移除后的结果产生一个输出迭代器
template <class _ForwardIter, class _Tp>
_ForwardIter remove(_ForwardIter __first, _ForwardIter __last,
const _Tp& __value) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
__STL_REQUIRES_BINARY_OP(_OP_EQUAL, bool,
typename iterator_traits<_ForwardIter>::value_type, _Tp);
__STL_CONVERTIBLE(_Tp, typename iterator_traits<_ForwardIter>::value_type);
__first = find(__first, __last, __value);
_ForwardIter __i = __first;
return __first == __last ? __first
: remove_copy(++__i, __last, __first, __value);
}
remove_copy：将删除的结果新产生一个输出迭代器
template <class _InputIter, class _OutputIter, class _Tp>
_OutputIter remove_copy(_InputIter __first, _InputIter __last,
_OutputIter __result, const _Tp& __value) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES_BINARY_OP(_OP_EQUAL, bool,
typename iterator_traits<_InputIter>::value_type, _Tp);
for ( ; __first != __last; ++__first)
if (!(*__first == __value)) {
*__result = *__first;
++__result;
}
return __result;
}
remove_if：满足一定条件的容器后的结果产生一个输出迭代器
template <class _ForwardIter, class _Predicate>
_ForwardIter remove_if(_ForwardIter __first, _ForwardIter __last,
_Predicate __pred) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
__STL_UNARY_FUNCTION_CHECK(_Predicate, bool,
typename iterator_traits<_ForwardIter>::value_type);
__first = find_if(__first, __last, __pred);
_ForwardIter __i = __first;
return __first == __last ? __first
: remove_copy_if(++__i, __last, __first, __pred);
}
remove_copy_if：满足一定条件的容器结果产生一个输出迭代器
template <class _InputIter, class _OutputIter, class _Predicate>
_OutputIter remove_copy_if(_InputIter __first, _InputIter __last,
_OutputIter __result, _Predicate __pred) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_UNARY_FUNCTION_CHECK(_Predicate, bool,
typename iterator_traits<_InputIter>::value_type);
for ( ; __first != __last; ++__first)
if (!__pred(*__first)) {
*__result = *__first;
++__result;
}
return __result;
}
replace：将[first，last）区间内所有的old_value都以new_value替代
template <class _ForwardIter, class _Tp>
void replace(_ForwardIter __first, _ForwardIter __last,
const _Tp& __old_value, const _Tp& __new_value) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
__STL_REQUIRES_BINARY_OP(_OP_EQUAL, bool,
typename iterator_traits<_ForwardIter>::value_type, _Tp);
__STL_CONVERTIBLE(_Tp, typename iterator_traits<_ForwardIter>::value_type);
for ( ; __first != __last; ++__first)
if (*__first == __old_value)
*__first = __new_value;
}
replace_copy：行为和replace类似，唯一的区别是会新产生一个序列
template <class _ForwardIter, class _Predicate, class _Tp>
void replace_if(_ForwardIter __first, _ForwardIter __last,
_Predicate __pred, const _Tp& __new_value) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
__STL_CONVERTIBLE(_Tp, typename iterator_traits<_ForwardIter>::value_type);
__STL_UNARY_FUNCTION_CHECK(_Predicate, bool,
typename iterator_traits<_ForwardIter>::value_type);
for ( ; __first != __last; ++__first)
if (__pred(*__first))
*__first = __new_value;
}
replace_if：将[first，last）区间内所有“被pred评估为true”的元素，都已新值替代
template <class _ForwardIter, class _Predicate, class _Tp>
void replace_if(_ForwardIter __first, _ForwardIter __last,
_Predicate __pred, const _Tp& __new_value) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
__STL_CONVERTIBLE(_Tp, typename iterator_traits<_ForwardIter>::value_type);
__STL_UNARY_FUNCTION_CHECK(_Predicate, bool,
typename iterator_traits<_ForwardIter>::value_type);
for ( ; __first != __last; ++__first)
if (__pred(*__first))
*__first = __new_value;
}
replace_copy_if：行为于replace_if类似，但是会产生一个新的序列
template <class _InputIter, class _OutputIter, class _Predicate, class _Tp>
_OutputIter replace_copy_if(_InputIter __first, _InputIter __last,
_OutputIter __result,
_Predicate __pred, const _Tp& __new_value) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_UNARY_FUNCTION_CHECK(_Predicate, bool,
typename iterator_traits<_InputIter>::value_type);
for ( ; __first != __last; ++__first, ++__result)
*__result = __pred(*__first) ? __new_value : *__first;
return __result;
}
reverse_copy：行为类似于reverse，但是会产生一个新的输出迭代器
template <class _BidirectionalIter, class _OutputIter>
_OutputIter reverse_copy(_BidirectionalIter __first,
_BidirectionalIter __last,
_OutputIter __result) {
__STL_REQUIRES(_BidirectionalIter, _BidirectionalIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
while (__first != __last) {
--__last;
*__result = *__last;
++__result;
}
return __result;
}
reverse：逆置序列
template <class _BidirectionalIter>
inline void reverse(_BidirectionalIter __first, _BidirectionalIter __last) {
__STL_REQUIRES(_BidirectionalIter, _Mutable_BidirectionalIterator);
__reverse(__first, __last, __ITERATOR_CATEGORY(__first));
}
template <class _RandomAccessIter>
void __reverse(_RandomAccessIter __first, _RandomAccessIter __last,
random_access_iterator_tag) {
while (__first < __last)
iter_swap(__first++, --__last);
}
rotate：将[first，middle）内的元素和[middle，last）内的元素互换，middle所指的元素会称为序列的第一个元素
template <class _ForwardIter, class _Distance>
_ForwardIter __rotate(_ForwardIter __first,
_ForwardIter __middle,
_ForwardIter __last,
_Distance*,
forward_iterator_tag) {
if (__first == __middle)
return __last;
if (__last == __middle)
return __first;
_ForwardIter __first2 = __middle;
do {
swap(*__first++, *__first2++);
if (__first == __middle)
__middle = __first2;
} while (__first2 != __last);
_ForwardIter __new_middle = __first;
__first2 = __middle;
while (__first2 != __last) {
swap (*__first++, *__first2++);
if (__first == __middle)
__middle = __first2;
else if (__first2 == __last)
__first2 = __middle;
}
return __new_middle;
}
template <class _BidirectionalIter, class _Distance>
_BidirectionalIter __rotate(_BidirectionalIter __first,
_BidirectionalIter __middle,
_BidirectionalIter __last,
_Distance*,
bidirectional_iterator_tag) {
__STL_REQUIRES(_BidirectionalIter, _Mutable_BidirectionalIterator);
if (__first == __middle)
return __last;
if (__last == __middle)
return __first;
__reverse(__first, __middle, bidirectional_iterator_tag());
__reverse(__middle, __last, bidirectional_iterator_tag());
while (__first != __middle && __middle != __last)
swap (*__first++, *--__last);
if (__first == __middle) {
__reverse(__middle, __last, bidirectional_iterator_tag());
return __last;
}
else {
__reverse(__first, __middle, bidirectional_iterator_tag());
return __first;
}
}
template <class _RandomAccessIter, class _Distance, class _Tp>
_RandomAccessIter __rotate(_RandomAccessIter __first,
_RandomAccessIter __middle,
_RandomAccessIter __last,
_Distance *, _Tp *) {
__STL_REQUIRES(_RandomAccessIter, _Mutable_RandomAccessIterator);
_Distance __n = __last - __first;
_Distance __k = __middle - __first;
_Distance __l = __n - __k;
_RandomAccessIter __result = __first + (__last - __middle);
if (__k == 0)
return __last;
else if (__k == __l) {
swap_ranges(__first, __middle, __middle);
return __result;
}
_Distance __d = __gcd(__n, __k);
for (_Distance __i = 0; __i < __d; __i++) {
_Tp __tmp = *__first;
_RandomAccessIter __p = __first;
if (__k < __l) {
for (_Distance __j = 0; __j < __l/__d; __j++) {
if (__p > __first + __l) {
*__p = *(__p - __l);
__p -= __l;
}
*__p = *(__p + __k);
__p += __k;
}
}
else {
for (_Distance __j = 0; __j < __k/__d - 1; __j ++) {
if (__p < __last - __k) {
*__p = *(__p + __k);
__p += __k;
}
*__p = * (__p - __l);
__p -= __l;
}
}
*__p = __tmp;
++__first;
}
return __result;
}
template <class _ForwardIter>
inline _ForwardIter rotate(_ForwardIter __first, _ForwardIter __middle,
_ForwardIter __last) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
return __rotate(__first, __middle, __last,
__DISTANCE_TYPE(__first),
__ITERATOR_CATEGORY(__first));
}
rotate_copy：和rotate类似，产生一个输出迭代器
template <class _ForwardIter, class _OutputIter>
_OutputIter rotate_copy(_ForwardIter __first, _ForwardIter __middle,
_ForwardIter __last, _OutputIter __result) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
return copy(__first, __middle, copy(__middle, __last, __result));
}
search：在序列一所涵盖的区间中，查找序列二的首次出现点
template <class _ForwardIter1, class _ForwardIter2>
_ForwardIter1 search(_ForwardIter1 __first1, _ForwardIter1 __last1,
_ForwardIter2 __first2, _ForwardIter2 __last2)
{
__STL_REQUIRES(_ForwardIter1, _ForwardIterator);
__STL_REQUIRES(_ForwardIter2, _ForwardIterator);
__STL_REQUIRES_BINARY_OP(_OP_EQUAL, bool,
typename iterator_traits<_ForwardIter1>::value_type,
typename iterator_traits<_ForwardIter2>::value_type);
// Test for empty ranges
if (__first1 == __last1 || __first2 == __last2)
return __first1;
// Test for a pattern of length 1.
_ForwardIter2 __tmp(__first2);
++__tmp;
if (__tmp == __last2)
return find(__first1, __last1, *__first2);
// General case.
_ForwardIter2 __p1, __p;
__p1 = __first2; ++__p1;
_ForwardIter1 __current = __first1;
while (__first1 != __last1) {
__first1 = find(__first1, __last1, *__first2);
if (__first1 == __last1)
return __last1;
__p = __p1;
__current = __first1;
if (++__current == __last1)
return __last1;
while (*__current == *__p) {
if (++__p == __last2)
return __first1;
if (++__current == __last1)
return __last1;
}
++__first1;
}
return __first1;
}
template <class _ForwardIter1, class _ForwardIter2, class _BinaryPred>
_ForwardIter1 search(_ForwardIter1 __first1, _ForwardIter1 __last1,
_ForwardIter2 __first2, _ForwardIter2 __last2,
_BinaryPred __predicate)
{
__STL_REQUIRES(_ForwardIter1, _ForwardIterator);
__STL_REQUIRES(_ForwardIter2, _ForwardIterator);
__STL_BINARY_FUNCTION_CHECK(_BinaryPred, bool,
typename iterator_traits<_ForwardIter1>::value_type,
typename iterator_traits<_ForwardIter2>::value_type);
// Test for empty ranges
if (__first1 == __last1 || __first2 == __last2)
return __first1;
// Test for a pattern of length 1.
_ForwardIter2 __tmp(__first2);
++__tmp;
if (__tmp == __last2) {
while (__first1 != __last1 && !__predicate(*__first1, *__first2))
++__first1;
return __first1;
}
// General case.
_ForwardIter2 __p1, __p;
__p1 = __first2; ++__p1;
_ForwardIter1 __current = __first1;
while (__first1 != __last1) {
while (__first1 != __last1) {
if (__predicate(*__first1, *__first2))
break;
++__first1;
}
while (__first1 != __last1 && !__predicate(*__first1, *__first2))
++__first1;
if (__first1 == __last1)
return __last1;
__p = __p1;
__current = __first1;
if (++__current == __last1) return __last1;
while (__predicate(*__current, *__p)) {
if (++__p == __last2)
return __first1;
if (++__current == __last1)
return __last1;
}
++__first1;
}
return __first1;
}
search_n：在序列[first，last）所涵盖的区间中，查找“连续count个符合条件之元素”所形成的子序列，并返回一个迭代器指向该子序列起始处
template <class _ForwardIter, class _Integer, class _Tp>
_ForwardIter search_n(_ForwardIter __first, _ForwardIter __last,
_Integer __count, const _Tp& __val) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES(typename iterator_traits<_ForwardIter>::value_type,
_EqualityComparable);
__STL_REQUIRES(_Tp, _EqualityComparable);
if (__count <= 0)
return __first;
else {
__first = find(__first, __last, __val);
while (__first != __last) {
_Integer __n = __count - 1;
_ForwardIter __i = __first;
++__i;
while (__i != __last && __n != 0 && *__i == __val) {
++__i;
--__n;
}
if (__n == 0)
return __first;
else
__first = find(__i, __last, __val);
}
return __last;
}
}
template <class _ForwardIter, class _Integer, class _Tp, class _BinaryPred>
_ForwardIter search_n(_ForwardIter __first, _ForwardIter __last,
_Integer __count, const _Tp& __val,
_BinaryPred __binary_pred) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_BINARY_FUNCTION_CHECK(_BinaryPred, bool,
typename iterator_traits<_ForwardIter>::value_type, _Tp);
if (__count <= 0)
return __first;
else {
while (__first != __last) {
if (__binary_pred(*__first, __val))
break;
++__first;
}
while (__first != __last) {
_Integer __n = __count - 1;
_ForwardIter __i = __first;
++__i;
while (__i != __last && __n != 0 && __binary_pred(*__i, __val)) {
++__i;
--__n;
}
if (__n == 0)
return __first;
else {
while (__i != __last) {
if (__binary_pred(*__i, __val))
break;
++__i;
}
__first = __i;
}
}
return __last;
}
}
swap_ranges：将[first，last）区间内的元素与“从first开始、个数相同”的元素互相交换，也可位于不同的容器中
template <class _ForwardIter1, class _ForwardIter2>
_ForwardIter2 swap_ranges(_ForwardIter1 __first1, _ForwardIter1 __last1,
_ForwardIter2 __first2) {
__STL_REQUIRES(_ForwardIter1, _Mutable_ForwardIterator);
__STL_REQUIRES(_ForwardIter2, _Mutable_ForwardIterator);
__STL_CONVERTIBLE(typename iterator_traits<_ForwardIter1>::value_type,
typename iterator_traits<_ForwardIter2>::value_type);
__STL_CONVERTIBLE(typename iterator_traits<_ForwardIter2>::value_type,
typename iterator_traits<_ForwardIter1>::value_type);
for ( ; __first1 != __last1; ++__first1, ++__first2)
iter_swap(__first1, __first2);
return __first2;
}
transform：以仿函数op作用于区间内的每一个元素，产生一个新序列
template <class _InputIter, class _OutputIter, class _UnaryOperation>
_OutputIter transform(_InputIter __first, _InputIter __last,
_OutputIter __result, _UnaryOperation __opr) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
for ( ; __first != __last; ++__first, ++__result)
*__result = __opr(*__first);
return __result;
}
template <class _InputIter1, class _InputIter2, class _OutputIter,
class _BinaryOperation>
_OutputIter transform(_InputIter1 __first1, _InputIter1 __last1,
_InputIter2 __first2, _OutputIter __result,
_BinaryOperation __binary_op) {
__STL_REQUIRES(_InputIter1, _InputIterator);
__STL_REQUIRES(_InputIter2, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
for ( ; __first1 != __last1; ++__first1, ++__first2, ++__result)
*__result = __binary_op(*__first1, *__first2);
return __result;
}
unique：移除重复的元素，当在序列中遇到重复元素群，移除第一个以后的元素
template <class _ForwardIter>
_ForwardIter unique(_ForwardIter __first, _ForwardIter __last) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
__STL_REQUIRES(typename iterator_traits<_ForwardIter>::value_type,
_EqualityComparable);
__first = adjacent_find(__first, __last);
return unique_copy(__first, __last, __first);
}
template <class _ForwardIter, class _BinaryPredicate>
_ForwardIter unique(_ForwardIter __first, _ForwardIter __last,
_BinaryPredicate __binary_pred) {
__STL_REQUIRES(_ForwardIter, _Mutable_ForwardIterator);
__STL_BINARY_FUNCTION_CHECK(_BinaryPredicate, bool,
typename iterator_traits<_ForwardIter>::value_type,
typename iterator_traits<_ForwardIter>::value_type);
__first = adjacent_find(__first, __last, __binary_pred);
return unique_copy(__first, __last, __first, __binary_pred);
}
unique_copy：产生一个新序列，和unique类似
template <class _InputIter, class _OutputIter, class _Tp>
_OutputIter __unique_copy(_InputIter __first, _InputIter __last,
_OutputIter __result, _Tp*) {
_Tp __value = *__first;
*__result = __value;
while (++__first != __last)
if (!(__value == *__first)) {
__value = *__first;
*++__result = __value;
}
return ++__result;
}
template <class _InputIter, class _OutputIter>
inline _OutputIter __unique_copy(_InputIter __first, _InputIter __last,
_OutputIter __result,
output_iterator_tag) {
return __unique_copy(__first, __last, __result, __VALUE_TYPE(__first));
}
template <class _InputIter, class _ForwardIter>
_ForwardIter __unique_copy(_InputIter __first, _InputIter __last,
_ForwardIter __result, forward_iterator_tag) {
*__result = *__first;
while (++__first != __last)
if (!(*__result == *__first))
*++__result = *__first;
return ++__result;
}
template <class _InputIter, class _OutputIter>
inline _OutputIter unique_copy(_InputIter __first, _InputIter __last,
_OutputIter __result) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
__STL_REQUIRES(typename iterator_traits<_InputIter>::value_type,
_EqualityComparable);
if (__first == __last) return __result;
return __unique_copy(__first, __last, __result,
__ITERATOR_CATEGORY(__result));
}
template <class _InputIter, class _OutputIter, class _BinaryPredicate,
class _Tp>
_OutputIter __unique_copy(_InputIter __first, _InputIter __last,
_OutputIter __result,
_BinaryPredicate __binary_pred, _Tp*) {
__STL_BINARY_FUNCTION_CHECK(_BinaryPredicate, bool, _Tp, _Tp);
_Tp __value = *__first;
*__result = __value;
while (++__first != __last)
if (!__binary_pred(__value, *__first)) {
__value = *__first;
*++__result = __value;
}
return ++__result;
}
template <class _InputIter, class _OutputIter, class _BinaryPredicate>
inline _OutputIter __unique_copy(_InputIter __first, _InputIter __last,
_OutputIter __result,
_BinaryPredicate __binary_pred,
output_iterator_tag) {
return __unique_copy(__first, __last, __result, __binary_pred,
__VALUE_TYPE(__first));
}
template <class _InputIter, class _ForwardIter, class _BinaryPredicate>
_ForwardIter __unique_copy(_InputIter __first, _InputIter __last,
_ForwardIter __result,
_BinaryPredicate __binary_pred,
forward_iterator_tag) {
__STL_BINARY_FUNCTION_CHECK(_BinaryPredicate, bool,
typename iterator_traits<_ForwardIter>::value_type,
typename iterator_traits<_InputIter>::value_type);
*__result = *__first;
while (++__first != __last)
if (!__binary_pred(*__result, *__first)) *++__result = *__first;
return ++__result;
}
template <class _InputIter, class _OutputIter, class _BinaryPredicate>
inline _OutputIter unique_copy(_InputIter __first, _InputIter __last,
_OutputIter __result,
_BinaryPredicate __binary_pred) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_OutputIter, _OutputIterator);
if (__first == __last) return __result;
return __unique_copy(__first, __last, __result, __binary_pred,
__ITERATOR_CATEGORY(__result));
}
复杂算法
lower_bound：应用于有序区间，二分查找的其他版本，如果查找存在则返回指向该元素的迭代器，如果不存在则返回一个迭代器，指向第一个“不小于value”的元素
template <class _ForwardIter, class _Tp, class _Distance>
_ForwardIter __lower_bound(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val, _Distance*)
{
_Distance __len = 0;
distance(__first, __last, __len);
_Distance __half;
_ForwardIter __middle;
while (__len > 0) {
__half = __len >> 1;
__middle = __first;
advance(__middle, __half);
if (*__middle < __val) {
__first = __middle;
++__first;
__len = __len - __half - 1;
}
else
__len = __half;
}
return __first;
}
template <class _ForwardIter, class _Tp>
inline _ForwardIter lower_bound(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES_SAME_TYPE(_Tp,
typename iterator_traits<_ForwardIter>::value_type);
__STL_REQUIRES(_Tp, _LessThanComparable);
return __lower_bound(__first, __last, __val,
__DISTANCE_TYPE(__first));
}
template <class _ForwardIter, class _Tp, class _Compare, class _Distance>
_ForwardIter __lower_bound(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val, _Compare __comp, _Distance*)
{
_Distance __len = 0;
distance(__first, __last, __len);
_Distance __half;
_ForwardIter __middle;
while (__len > 0) {
__half = __len >> 1;
__middle = __first;
advance(__middle, __half);
if (__comp(*__middle, __val)) {
__first = __middle;
++__first;
__len = __len - __half - 1;
}
else
__len = __half;
}
return __first;
}
template <class _ForwardIter, class _Tp, class _Compare>
inline _ForwardIter lower_bound(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val, _Compare __comp) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES_SAME_TYPE(_Tp,
typename iterator_traits<_ForwardIter>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool, _Tp, _Tp);
return __lower_bound(__first, __last, __val, __comp,
__DISTANCE_TYPE(__first));
}
upper_bound：于lower_bound类似，如果找到了返回value可被插入的“最后一个”合适位置，而非指向他的本身
template <class _ForwardIter, class _Tp, class _Distance>
_ForwardIter __upper_bound(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val, _Distance*)
{
_Distance __len = 0;
distance(__first, __last, __len);
_Distance __half;
_ForwardIter __middle;
while (__len > 0) {
__half = __len >> 1;
__middle = __first;
advance(__middle, __half);
if (__val < *__middle)
__len = __half;
else {
__first = __middle;
++__first;
__len = __len - __half - 1;
}
}
return __first;
}
template <class _ForwardIter, class _Tp>
inline _ForwardIter upper_bound(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES_SAME_TYPE(_Tp,
typename iterator_traits<_ForwardIter>::value_type);
__STL_REQUIRES(_Tp, _LessThanComparable);
return __upper_bound(__first, __last, __val,
__DISTANCE_TYPE(__first));
}
template <class _ForwardIter, class _Tp, class _Compare, class _Distance>
_ForwardIter __upper_bound(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val, _Compare __comp, _Distance*)
{
_Distance __len = 0;
distance(__first, __last, __len);
_Distance __half;
_ForwardIter __middle;
while (__len > 0) {
__half = __len >> 1;
__middle = __first;
advance(__middle, __half);
if (__comp(__val, *__middle))
__len = __half;
else {
__first = __middle;
++__first;
__len = __len - __half - 1;
}
}
return __first;
}
template <class _ForwardIter, class _Tp, class _Compare>
inline _ForwardIter upper_bound(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val, _Compare __comp) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES_SAME_TYPE(_Tp,
typename iterator_traits<_ForwardIter>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool, _Tp, _Tp);
return __upper_bound(__first, __last, __val, __comp,
__DISTANCE_TYPE(__first));
}
binary_search：应用于有序区间，找到了返回true，找不到返回false
template <class _ForwardIter, class _Tp>
bool binary_search(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES_SAME_TYPE(_Tp,
typename iterator_traits<_ForwardIter>::value_type);
__STL_REQUIRES(_Tp, _LessThanComparable);
_ForwardIter __i = lower_bound(__first, __last, __val);
return __i != __last && !(__val < *__i);
}
template <class _ForwardIter, class _Tp, class _Compare>
bool binary_search(_ForwardIter __first, _ForwardIter __last,
const _Tp& __val,
_Compare __comp) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES_SAME_TYPE(_Tp,
typename iterator_traits<_ForwardIter>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool, _Tp, _Tp);
_ForwardIter __i = lower_bound(__first, __last, __val, __comp);
return __i != __last && !__comp(__val, *__i);
}
next_permutation：下一个排列组合
prev_permutation：前一个排列组合
random_shuffle：将序列中元素随机重排
template <class _RandomAccessIter>
inline void random_shuffle(_RandomAccessIter __first,
_RandomAccessIter __last) {
__STL_REQUIRES(_RandomAccessIter, _Mutable_RandomAccessIterator);
if (__first == __last) return;
for (_RandomAccessIter __i = __first + 1; __i != __last; ++__i)
iter_swap(__i, __first + __random_number((__i - __first) + 1));
}
template <class _RandomAccessIter, class _RandomNumberGenerator>
void random_shuffle(_RandomAccessIter __first, _RandomAccessIter __last,
_RandomNumberGenerator& __rand) {
__STL_REQUIRES(_RandomAccessIter, _Mutable_RandomAccessIterator);
if (__first == __last) return;
for (_RandomAccessIter __i = __first + 1; __i != __last; ++__i)
iter_swap(__i, __first + __rand((__i - __first) + 1));
}
partial_sort：选择一个middle，重排[first，last），使得middle-first个最小元素以递增顺序排序，置于[first-middle）中，其余的放在[middle，last）中
template <class _RandomAccessIter, class _Tp>
void __partial_sort(_RandomAccessIter __first, _RandomAccessIter __middle,
_RandomAccessIter __last, _Tp*) {
make_heap(__first, __middle);
for (_RandomAccessIter __i = __middle; __i < __last; ++__i)
if (*__i < *__first)
__pop_heap(__first, __middle, __i, _Tp(*__i),
__DISTANCE_TYPE(__first));
sort_heap(__first, __middle);
}
template <class _RandomAccessIter>
inline void partial_sort(_RandomAccessIter __first,
_RandomAccessIter __middle,
_RandomAccessIter __last) {
__STL_REQUIRES(_RandomAccessIter, _Mutable_RandomAccessIterator);
__STL_REQUIRES(typename iterator_traits<_RandomAccessIter>::value_type,
_LessThanComparable);
__partial_sort(__first, __middle, __last, __VALUE_TYPE(__first));
}
template <class _RandomAccessIter, class _Tp, class _Compare>
void __partial_sort(_RandomAccessIter __first, _RandomAccessIter __middle,
_RandomAccessIter __last, _Tp*, _Compare __comp) {
make_heap(__first, __middle, __comp);
for (_RandomAccessIter __i = __middle; __i < __last; ++__i)
if (__comp(*__i, *__first))
__pop_heap(__first, __middle, __i, _Tp(*__i), __comp,
__DISTANCE_TYPE(__first));
sort_heap(__first, __middle, __comp);
}
template <class _RandomAccessIter, class _Compare>
inline void partial_sort(_RandomAccessIter __first,
_RandomAccessIter __middle,
_RandomAccessIter __last, _Compare __comp) {
__STL_REQUIRES(_RandomAccessIter, _Mutable_RandomAccessIterator);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_RandomAccessIter>::value_type,
typename iterator_traits<_RandomAccessIter>::value_type);
__partial_sort(__first, __middle, __last, __VALUE_TYPE(__first), __comp);
}
partial_sort_copy：于partial_sort类似，不过是产生一个新的空间放元素
template <class _InputIter, class _RandomAccessIter, class _Distance,
class _Tp>
_RandomAccessIter __partial_sort_copy(_InputIter __first,
_InputIter __last,
_RandomAccessIter __result_first,
_RandomAccessIter __result_last,
_Distance*, _Tp*) {
if (__result_first == __result_last) return __result_last;
_RandomAccessIter __result_real_last = __result_first;
while(__first != __last && __result_real_last != __result_last) {
*__result_real_last = *__first;
++__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),
_Tp(*__first));
++__first;
}
sort_heap(__result_first, __result_real_last);
return __result_real_last;
}
template <class _InputIter, class _RandomAccessIter>
inline _RandomAccessIter
partial_sort_copy(_InputIter __first, _InputIter __last,
_RandomAccessIter __result_first,
_RandomAccessIter __result_last) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_RandomAccessIter, _Mutable_RandomAccessIterator);
__STL_CONVERTIBLE(typename iterator_traits<_InputIter>::value_type,
typename iterator_traits<_RandomAccessIter>::value_type);
__STL_REQUIRES(typename iterator_traits<_RandomAccessIter>::value_type,
_LessThanComparable);
__STL_REQUIRES(typename iterator_traits<_InputIter>::value_type,
_LessThanComparable);
return __partial_sort_copy(__first, __last, __result_first, __result_last,
__DISTANCE_TYPE(__result_first),
__VALUE_TYPE(__first));
}
template <class _InputIter, class _RandomAccessIter, class _Compare,
class _Distance, class _Tp>
_RandomAccessIter __partial_sort_copy(_InputIter __first,
_InputIter __last,
_RandomAccessIter __result_first,
_RandomAccessIter __result_last,
_Compare __comp, _Distance*, _Tp*) {
if (__result_first == __result_last) return __result_last;
_RandomAccessIter __result_real_last = __result_first;
while(__first != __last && __result_real_last != __result_last) {
*__result_real_last = *__first;
++__result_real_last;
++__first;
}
make_heap(__result_first, __result_real_last, __comp);
while (__first != __last) {
if (__comp(*__first, *__result_first))
__adjust_heap(__result_first, _Distance(0),
_Distance(__result_real_last - __result_first),
_Tp(*__first),
__comp);
++__first;
}
sort_heap(__result_first, __result_real_last, __comp);
return __result_real_last;
}
template <class _InputIter, class _RandomAccessIter, class _Compare>
inline _RandomAccessIter
partial_sort_copy(_InputIter __first, _InputIter __last,
_RandomAccessIter __result_first,
_RandomAccessIter __result_last, _Compare __comp) {
__STL_REQUIRES(_InputIter, _InputIterator);
__STL_REQUIRES(_RandomAccessIter, _Mutable_RandomAccessIterator);
__STL_CONVERTIBLE(typename iterator_traits<_InputIter>::value_type,
typename iterator_traits<_RandomAccessIter>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_RandomAccessIter>::value_type,
typename iterator_traits<_RandomAccessIter>::value_type);
return __partial_sort_copy(__first, __last, __result_first, __result_last,
__comp,
__DISTANCE_TYPE(__result_first),
__VALUE_TYPE(__first));
}
sort：很精彩，我前面博客已经分析过，在此不做叙述了
equal_range：应用于有序区间，试图在已排序的区间中寻找value，返回一对迭代器i和j，i是在不破坏次序的前提下，value值可插入的第一个位置，j是在不破坏次序的前提下，value值可插入的最后一个位置
template <class _ForwardIter, class _Tp, class _Distance>
pair<_ForwardIter, _ForwardIter>
__equal_range(_ForwardIter __first, _ForwardIter __last, const _Tp& __val,
_Distance*)
{
_Distance __len = 0;
distance(__first, __last, __len);
_Distance __half;
_ForwardIter __middle, __left, __right;
while (__len > 0) {
__half = __len >> 1;
__middle = __first;
advance(__middle, __half);
if (*__middle < __val) {
__first = __middle;
++__first;
__len = __len - __half - 1;
}
else if (__val < *__middle)
__len = __half;
else {
__left = lower_bound(__first, __middle, __val);
advance(__first, __len);
__right = upper_bound(++__middle, __first, __val);
return pair<_ForwardIter, _ForwardIter>(__left, __right);
}
}
return pair<_ForwardIter, _ForwardIter>(__first, __first);
}
template <class _ForwardIter, class _Tp>
inline pair<_ForwardIter, _ForwardIter>
equal_range(_ForwardIter __first, _ForwardIter __last, const _Tp& __val) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES_SAME_TYPE(_Tp,
typename iterator_traits<_ForwardIter>::value_type);
__STL_REQUIRES(_Tp, _LessThanComparable);
return __equal_range(__first, __last, __val,
__DISTANCE_TYPE(__first));
}
template <class _ForwardIter, class _Tp, class _Compare, class _Distance>
pair<_ForwardIter, _ForwardIter>
__equal_range(_ForwardIter __first, _ForwardIter __last, const _Tp& __val,
_Compare __comp, _Distance*)
{
_Distance __len = 0;
distance(__first, __last, __len);
_Distance __half;
_ForwardIter __middle, __left, __right;
while (__len > 0) {
__half = __len >> 1;
__middle = __first;
advance(__middle, __half);
if (__comp(*__middle, __val)) {
__first = __middle;
++__first;
__len = __len - __half - 1;
}
else if (__comp(__val, *__middle))
__len = __half;
else {
__left = lower_bound(__first, __middle, __val, __comp);
advance(__first, __len);
__right = upper_bound(++__middle, __first, __val, __comp);
return pair<_ForwardIter, _ForwardIter>(__left, __right);
}
}
return pair<_ForwardIter, _ForwardIter>(__first, __first);
}
template <class _ForwardIter, class _Tp, class _Compare>
inline pair<_ForwardIter, _ForwardIter>
equal_range(_ForwardIter __first, _ForwardIter __last, const _Tp& __val,
_Compare __comp) {
__STL_REQUIRES(_ForwardIter, _ForwardIterator);
__STL_REQUIRES_SAME_TYPE(_Tp,
typename iterator_traits<_ForwardIter>::value_type);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool, _Tp, _Tp);
return __equal_range(__first, __last, __val, __comp,
__DISTANCE_TYPE(__first));
}
inplace_merge：应用于有序区间，将两个有序的序列合并成一个新的有序序列
template <class _BidirectionalIter, class _Tp, class _Distance>
inline void __inplace_merge_aux(_BidirectionalIter __first,
_BidirectionalIter __middle,
_BidirectionalIter __last, _Tp*, _Distance*) {
_Distance __len1 = 0;
distance(__first, __middle, __len1);
_Distance __len2 = 0;
distance(__middle, __last, __len2);
_Temporary_buffer<_BidirectionalIter, _Tp> __buf(__first, __last);
if (__buf.begin() == 0)
__merge_without_buffer(__first, __middle, __last, __len1, __len2);
else
__merge_adaptive(__first, __middle, __last, __len1, __len2,
__buf.begin(), _Distance(__buf.size()));
}
template <class _BidirectionalIter, class _Tp,
class _Distance, class _Compare>
inline void __inplace_merge_aux(_BidirectionalIter __first,
_BidirectionalIter __middle,
_BidirectionalIter __last, _Tp*, _Distance*,
_Compare __comp) {
_Distance __len1 = 0;
distance(__first, __middle, __len1);
_Distance __len2 = 0;
distance(__middle, __last, __len2);
_Temporary_buffer<_BidirectionalIter, _Tp> __buf(__first, __last);
if (__buf.begin() == 0)
__merge_without_buffer(__first, __middle, __last, __len1, __len2, __comp);
else
__merge_adaptive(__first, __middle, __last, __len1, __len2,
__buf.begin(), _Distance(__buf.size()),
__comp);
}
template <class _BidirectionalIter>
inline void inplace_merge(_BidirectionalIter __first,
_BidirectionalIter __middle,
_BidirectionalIter __last) {
__STL_REQUIRES(_BidirectionalIter, _Mutable_BidirectionalIterator);
__STL_REQUIRES(typename iterator_traits<_BidirectionalIter>::value_type,
_LessThanComparable);
if (__first == __middle || __middle == __last)
return;
__inplace_merge_aux(__first, __middle, __last,
__VALUE_TYPE(__first), __DISTANCE_TYPE(__first));
}
template <class _BidirectionalIter, class _Compare>
inline void inplace_merge(_BidirectionalIter __first,
_BidirectionalIter __middle,
_BidirectionalIter __last, _Compare __comp) {
__STL_REQUIRES(_BidirectionalIter, _Mutable_BidirectionalIterator);
__STL_BINARY_FUNCTION_CHECK(_Compare, bool,
typename iterator_traits<_BidirectionalIter>::value_type,
typename iterator_traits<_BidirectionalIter>::value_type);
if (__first == __middle || __middle == __last)
return;
__inplace_merge_aux(__first, __middle, __last,
__VALUE_TYPE(__first), __DISTANCE_TYPE(__first),
__comp);
}
merge sort：综合了sort和inplace_sort的优点
看看就得了，主要的还是得用！
