/*
stl_numeric.h
@功能，算术运算
日期，2012年10月23日 星期二
博客，http://blog.csdn.net/shunqiziranhao007/article/details/8138284
环境，win7-32-vs2010
*/
/* NOTE: This is an internal header file, included by other STL headers.
* You should not attempt to use it directly.
*/
#ifndef __SGI_STL_INTERNAL_NUMERIC_H
#define __SGI_STL_INTERNAL_NUMERIC_H
__STL_BEGIN_NAMESPACE
// 累加，一段元素，参3初值
template <class _InputIterator, class _Tp>
_Tp accumulate(_InputIterator __first, _InputIterator __last, _Tp __init)
{
__STL_REQUIRES(_InputIterator, _InputIterator);
for ( ; __first != __last; ++__first)
__init = __init + *__first;
return __init;
}
// 累加，一段元素，参3初值，参4元素间的运算符
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;
}
// returns the sum of the element-wise products and adds to it the
// specified initial value. So for ranges of values ai and bi, it returns:
// _Val + ( a1 * b1 ) + ( a2 * b2 ) +
// by iteratively replacing _Val with _Val + (*ai * *bi ).
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;
}
// _Val _Binary_op1 ( a1 _Binary_op2 b1 ) _Binary_op1 ( a2 _Binary_op2 b2 ) _Binary_op1
// by iteratively replacing _Val with _Val _Binary_op1 (*ai _Binary_op2 *bi ).
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;
}
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;
}
// 每加一个元素的值就记录结果
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);
}
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;
}
// 前后元素作差结果依次保存在参3中
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;
}
// 前后两个元素应用参4运算符
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);
}
// Returns __x ** __n, where __n >= 0. _Note that "multiplication"
// is required to be associative, but not necessarily commutative.
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);
}
// x的n次方
template <class _Tp, class _Integer>
inline _Tp power(_Tp __x, _Integer __n)
{
return __power(__x, __n);
}
// iota is not part of the C++ standard. It is an extension.
// 每个元素加上参3的值
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++;
}
__STL_END_NAMESPACE
#endif /* __SGI_STL_INTERNAL_NUMERIC_H */
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// mode:C++
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