```
template <class InputIterator, class OutputIterator>
OutputIterator partial_sum(
InputIterator first, InputIterator last,
OutputIterator result);
template
<class InputIterator, class OutputIterator, class BinaryOperation>
OutputIterator partial_sum(
InputIterator first, InputIterator last,
OutputIterator result, BinaryOperation binary_op);
```

*Effects:* For a non-empty range,
the function creates an accumulator acc whose type is InputIterator's
value type, initializes it with *first,
and assigns the result to *result. For every iterator i in [first + 1,last)
in order, acc is then modified by acc = acc + *i or acc = binary_op(acc, *i)
and the result is assigned to *(result + (i - first)).

*Returns:*
result + (last - first).

*Complexity:*
Exactly
(last - first) - 1
applications of
the binary operation.

*Requires:*
InputIterator's value type shall be constructible from the type of *first.
The result of the expression acc + *i or binary_op(acc, *i) shall be
implicitly convertible to InputIterator's value type. acc
shall be writable to the result output iterator.
In the ranges
[first,last]
and
[result,result + (last - first)]
binary_op
shall neither modify elements nor invalidate iterators or subranges.292

*Remarks:*
result
may be equal to
first.

The use of fully closed ranges is intentional.