std::advance
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                    | Defined in header  <iterator> | ||
| template< class InputIt, class Distance > void advance( InputIt& it, Distance n ); | (until C++17) | |
| template< class InputIt, class Distance > constexpr void advance( InputIt& it, Distance n ); | (since C++17) | |
Increments given iterator it by n elements.
If n is negative, the iterator is decremented. In this case, InputIt must meet the requirements of BidirectionalIterator, otherwise the behavior is undefined.
| Contents | 
[edit] Parameters
| it | - | iterator to be advanced | 
| n | - | number of elements itshould be advanced | 
| Type requirements | ||
| - InputItmust meet the requirements ofInputIterator. | ||
[edit] Return value
(none)
[edit] Complexity
Linear.
However, if InputIt additionally meets the requirements of RandomAccessIterator, complexity is constant.
[edit] Notes
The behavior is undefined if the specified sequence of increments or decrements would require that a non-incrementable iterator (such as the past-the-end iterator) is incremented, or that a non-decrementable iterator (such as the front iterator or the singular iterator) is decremented.
[edit] Example
Run this code
#include <iostream> #include <iterator> #include <vector> int main() { std::vector<int> v{ 3, 1, 4 }; auto vi = v.begin(); std::advance(vi, 2); std::cout << *vi << '\n'; }
Output:
4
[edit] See also
| (C++11) | increment an iterator (function) | 
| returns the distance between two iterators (function) | 


