Assign value of one iterator into another iterator C++

Question

Say I have an iterator it which is pointing to some element of map.
Also I have another iterator it1 , and I want to do something like this

it1 = it + 1;

How can we achieve this in C++ as above statement gives error in C++.

Bidirectional iterators don't support operator+. std::next would do that. — Qaz
– Qaz, Commented Nov 2, 2012 at 19:53
@Dave, For some reason, I was considering the possibility of using two different iterator types, but looking back, that seems pretty unlikely. — Qaz
– Qaz, Commented Nov 2, 2012 at 19:58

Kerrek SB · Accepted Answer · 2012-11-02 19:56:13Z

5

In C++11, you say auto it1 = std::next(it, 1);.

Prior to that, you have to say something like:

std::map<K, T>::iterator it1 = it;
std::advance(it1, 1);

Don't forget to #include <iterator>.

answered Nov 2, 2012 at 19:56

Kerrek SB

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1 Comment

Note you can just say std::next(it), the second param is defaulted to 1