C ++：用迭代器调用的vector :: erase

Question

I am working on a vector of structs.

When I am trying to call this function with iterator, like this:

vec2.erase (vec2.begin()+iter2);

it sends me this error:

"no match for 'operator+' in '(+vec2)->std::vector<_Tp, _Alloc>::begin [with _Tp = wordstype, _Alloc = std::allocator<wordstype>]() + iter2'" 

Can I send an iterator (or any other parameter)? If yes, what is the problem?

Answer 1

You cannot add iterator to iterator .

iter2 already points to the concrete place in a vector, so you can write:

iter2 = vec2.erase(iter2);

instead.

Answer 2

Yes erase can work with iterator and the code will look like:

erase(itr2);

You can also do:

erase(vec2.begin() + 3);

However the iterators do not declare operator+ so your call is not valid.

Answer 3

You are trying to add together two iterators, which makes no sense.

Post your code and explain what your are trying to do.

Answer 4

The problem you describe doesn't seem to have anything with std::vector<>::erase , according to the error message.

The expression the compiler has problems with is vec2.begin() + iter2 . Apparently, iter2 in your case is an iterator. vec2.begin() is also an iterator. You cannot add one iterator to another. It simply makes no sense. Hence the error.

What are you trying to do by vec2.begin() + iter2 ? If iter2 is indeed an iterator, why are you trying to add it to vec2.begin() ?