Defined in header
<iterator> | ||
---|---|---|
template< class ForwardIt > ForwardIt next( ForwardIt it, typename std::iterator_traits<ForwardIt>::difference_type n = 1 ); | (since C++11) (until C++17) | |
template< class InputIt > constexpr InputIt next( InputIt it, typename std::iterator_traits<InputIt>::difference_type n = 1 ); | (since C++17) |
Return the n
th successor of iterator it
.
it | - | an iterator |
n | - | number of elements to advance |
Type requirements | ||
-
ForwardIt must meet the requirements of ForwardIterator . |
||
-
InputIt must meet the requirements of InputIterator . |
The n
th successor of iterator it
.
template<class ForwardIt> ForwardIt next(ForwardIt it, typename std::iterator_traits<ForwardIt>::difference_type n = 1) { std::advance(it, n); return it; } |
Although the expression ++c.begin()
often compiles, it is not guaranteed to do so: c.begin()
is an rvalue expression, and there is no BidirectionalIterator
requirement that specifies that increment of an rvalue is guaranteed to work. In particular, when iterators are implemented as pointers, ++c.begin()
does not compile, while std::next(c.begin())
does.
#include <iostream> #include <iterator> #include <vector> int main() { std::vector<int> v{ 3, 1, 4 }; auto it = v.begin(); auto nx = std::next(it, 2); std::cout << *it << ' ' << *nx << '\n'; }
Output:
3 4
(C++11)
| decrement an iterator (function) |
advances an iterator by given distance (function) |
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