Unfortunately std::queue adapts the function known as push_back to just push which means that the standard back_insert_iterator doesn t work.

Probably the simplest way (albeit conceptually ugly) is to adapt the container adapter with a short lived container adapter adapter[sic] (eugh!) that lives as long as the back insert iterator.

template<class T>
class QueueAdapter
{
public:
    QueueAdapter(std::queue<T>& q) : _q(q) {}
    void push_back(const T& t) { _q.push(t); }

private:
    std::queue<T>& _q;
};

Used like this:

std::queue<int> qi;

QueueAdapter< std::queue<int> > qiqa( qi );

std::copy( v.begin(), v.end(), std::back_inserter( qiqa ) );

Queue does not allow iteration through its elements.

From the SGI STL Docs:

A queue is an adaptor that provides a restricted subset of Container functionality A queue is a "first in first out" (FIFO) data structure. 1 That is, elements are added to the back of the queue and may be removed from the front; Q.front() is the element that was added to the queue least recently. Queue does not allow iteration through its elements. [2]

You can make this work, but you can t use insert_iterator. You ll have to write something like queue_inserter that presents an iterator interface.

Update I couldn t help myself and deicded to try to implement the iterator you need. Here are the results:

template< typename T, typename U >
class queue_inserter {
    queue<T, U> &qu;  
public:
    queue_inserter(queue<T,U> &q) : qu(q) { }
    queue_inserter<T,U> operator ++ (int) { return *this; }
    queue_inserter<T,U> operator * () { return *this; }
    void operator = (const T &val) { qu.push(val); }
};

template< typename T, typename U >
queue_inserter<T,U> make_queue_inserter(queue<T,U> &q) {
    return queue_inserter<T,U>(q);
}    

This works great for functions like this:

template<typename II, typename OI>
void mycopy(II b, II e, OI oi) {
    while (b != e) { *oi++ = *b++; }
}

But it doesn t work with the STL copy because the STL is stupid.

std::queue isn t a container in the STL sense, it s a container adapter with very limited functionality. For what you seem to need either std::vector or std::deque ("double-ended queue, which is a "real container"), seems the right choice.

I m pretty sure it just won t work -- a queue provides push, but an insert iterator expects to use push_front or push_back. There s no real reason you couldn t write your own push_insert_iterator (or whatever name you prefer) but it is a bit of a pain...

insert_iterator and back_insert_iterator only work on containers (or adaptors) with (respectively) insert and push_back methods - queue doesn t have these. You could write your own iterator modelled on these, something like this:

template <typename Container> 
class push_iterator : public iterator<output_iterator_tag,void,void,void,void>
{
public:
    explicit push_iterator(Container &c) : container(c) {}

    push_iterator &operator*() {return *this;}
    push_iterator &operator++() {return *this;}
    push_iterator &operator++(int) {return *this;}

    push_iterator &operator=(typename Container::const_reference value)
    {
         container.push(value);
         return *this;
    }
private:
    Container &container;
};

Unless such a thing already exists, but I m pretty sure it doesn t.

std::queue is not one of the basic containers in STL. It is a container adaptor which is built using one of the basic STL containers ( in this case one of the sequential container either std::vector std::deque or std::list). It is designed specifically for FIFO behaviour and does not provide random insertion at the given iterator which you want for the insert_iterator to work. Hence it will not be possible to use queue like this.

The easiest way I could think of to do this is to:

class PushFunctor
{
public:
    PushFunctor(std::queue<int>& q) : myQ(q)
    {
    }
    void operator()(int n)
    {
        myQ.push(n);
    }

private:
    std::queue<int>& myQ;
};

And use it like:

queue<int> q;
PushFunctor p(q);
std::for_each(v.begin(), v.end(), p);

What you need is a push_inserter (i.e. an inserter that performs pushes into the queue). As far as I know, there is no such iterator in the STL. What I usually do is sadly fall back to the good old for loop.

If you have the courage, you can roll your own iterator, something along these lines:

template <typename Container>
class push_insert_iterator
{
  public:
    typedef Container                      container_type;
    typedef typename Container::value_type value_type;

    explicit push_insert_iterator(container_type & c)
        : container(c)
    {}    // construct with container

    push_insert_iterator<container_type> & operator=(const value_type & v)
    {
        //push value into the queue
        container.push(v);
        return (*this);
    }

    push_insert_iterator<container_type> & operator*()
    {
        return (*this);
    }

    push_insert_iterator<container_type> & operator++()
    {
        // Do nothing
        return (*this);
    }

    push_insert_iterator<container_type> operator++(int)
    {
        // Do nothing
        return (*this);
    }

  protected:
    container_type & container;    // reference to container
};

template <typename Container>
inline push_insert_iterator<Container> push_inserter(Container & c)
{
    return push_insert_iterator<Container>(c);
}

This is just a draft but you got the idea. Works with any container (or, well, container adapters) with a push method (e.g. queue, stack).

for c++11

std::for_each( v.begin(), v.end(), [&q1](int data) {  q1.push(data); }  );

and c++14

std::for_each( v.begin(), v.end(), [&q1](auto data) {  q1.push(data); }  );

In this simple case, you can write:

vector<int> v;
v.push_back( 1 );
v.push_back( 2 );

queue<int, vector<int> > q(v);

This will make a copy of the vector and use it as the underlying container of the queue.

Of course, this approach won t work if you need to enqueue things after the queue has been constructed.