std::deque<T,Allocator>::insert
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| (1) | ||
| iterator insert( iterator pos, const T& value ); | (until C++11) | |
| iterator insert( const_iterator pos, const T& value ); | (since C++11) | |
| iterator insert( const_iterator pos, T&& value ); | (2) | (since C++11) | 
| (3) | ||
| void insert( iterator pos, size_type count, const T& value ); | (until C++11) | |
| iterator insert( const_iterator pos, size_type count, const T& value ); | (since C++11) | |
| (4) | ||
| template< class InputIt > void insert( iterator pos, InputIt first, InputIt last ); | (until C++11) | |
| template< class InputIt > iterator insert( const_iterator pos, | (since C++11) | |
| iterator insert( const_iterator pos, std::initializer_list<T> ilist ); | (5) | (since C++11) | 
Inserts elements at the specified location in the container.
1-2) inserts 
value before pos3) inserts 
count copies of the value before pos4) inserts elements from range 
The behavior is undefined if 
[first, last) before pos. 
 | This overload has the same effect as overload (3) if  | (until C++11) | 
| This overload participates in overload resolution only if  | (since C++11) | 
first and last are iterators into *this. 5) inserts elements from initializer list 
ilist before pos.All iterators, including the past-the-end iterator, are invalidated. References are invalidated too, unless pos == begin() or pos == end(), in which case they are not invalidated.
Parameters
| pos | - | iterator before which the content will be inserted. posmay be the end() iterator | 
| value | - | element value to insert | 
| first, last | - | the range of elements to insert, can't be iterators into container for which insert is called | 
| ilist | - | initializer list to insert the values from | 
| Type requirements | ||
| - Tmust meet the requirements of CopyAssignable and CopyInsertable in order to use overload (1). | ||
| - Tmust meet the requirements of MoveAssignable and MoveInsertable in order to use overload (2). | ||
| - Tmust meet the requirements of CopyAssignable and CopyInsertable in order to use overload (3). | ||
| - Tmust meet the requirements of EmplaceConstructible in order to use overload (4,5). | ||
| - Tmust meet the requirements of Swappable, MoveAssignable, MoveConstructible and MoveInsertable in order to use overload (4,5). (since C++17) | ||
Return value
1-2) Iterator pointing to the inserted 
value3) Iterator pointing to the first element inserted, or 
pos if count==0.4) Iterator pointing to the first element inserted, or 
pos if first==last.5) Iterator pointing to the first element inserted, or 
pos if ilist is empty.Complexity
1-2) Constant plus linear in the lesser of the distances between 
pos and either of the ends of the container.3) Linear in count  plus linear in the lesser of the distances between 
pos and either of the ends of the container.4) Linear in std::distance(first, last) plus linear in the lesser of the distances between 
pos and either of the ends of the container.5) Linear in ilist.size() plus linear in the lesser of the distances between 
pos and either of the ends of the container.Exceptions
If an exception is thrown when inserting a single element at either end, this function has no effect (strong exception guarantee).
See also
| (C++11) | constructs element in-place (public member function) | 
| inserts an element to the beginning (public member function) | |
| adds an element to the end (public member function) |