std::partial_sum

Template:cpp/algorithm/sidebar Template:ddcl list begin <tr class="t-dsc-header">

<td>

Defined in header <numeric>

</td>

<td></td> <td></td> </tr> <tr class="t-dcl ">

<td >

template< class InputIterator, class OutputIterator >
OutputIterator partial_sum( InputIterator first, InputIterator last, OutputIterator d_first );

</td>

<td > (1) </td> <td class="t-dcl-nopad"> </td> </tr> <tr class="t-dcl ">

<td >

template< class InputIterator, class OutputIterator, class BinaryOperation >

OutputIterator partial_sum( InputIterator first, InputIterator last, OutputIterator d_first,

                            BinaryOperation op );

</td>

<td > (2) </td> <td class="t-dcl-nopad"> </td> </tr> Template:ddcl list end

Computes the partial sums of the elements in the subranges of the range [first, last) and writes them to the range beginning at d_first. The first version uses operator+ to sum up the elements, the second version uses the given binary function op.

Equivalent operation:

*(d_first)   = *first;
*(d_first+1) = *first + *(first+1);
*(d_first+2) = *first + *(first+1) + *(first+2);
*(d_first+3) = *first + *(first+1) + *(first+2) + *(first+3);
...

Parameters

first, last	-	the range of elements to sum
d_first	-	the beginning of the destination range
op	-	binary operation function object that will be applied. The signature of the function should be equivalent to the following:  Ret fun(const Type1 &a, const Type2 &b); The signature does not need to have const &. The type  Type1 must be such that an object of type iterator_traits<InputIterator>::value_type can be implicitly converted to  Type1. The type  Type2 must be such that an object of type InputIterator can be dereferenced and then implicitly converted to  Type2. The type Ret must be such that an object of type iterator_traits<InputIterator>::value_type can be assigned a value of type Ret. ​

Return value

Iterator to the element past the last element written.

Complexity

Exactly (last - first) - 1 applications of the binary operation

See also

Template:cpp/algorithm/dcl list adjacent differenceTemplate:cpp/algorithm/dcl list accumulate