std::deque::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, InputIt first, InputIt last ); | (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 pos
3) inserts 
count copies of the value before pos
4) inserts elements from range 
The behavior is undefined if 
[first, last) before pos. 
 | This overload has the same effect as overload (3) if InputItis an integral type. | (until C++11) | 
| This overload only participates in overload resolution if InputItqualifies asInputIterator, to avoid ambiguity with the overload (3). | (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.
| Contents | 
[edit] 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 ofCopyAssignableandCopyInsertablein order to use overload (1). | ||
| - Tmust meet the requirements ofMoveAssignableandMoveInsertablein order to use overload (2). | ||
| - Tmust meet the requirements ofCopyAssignableandCopyInsertablein order to use overload (3). | ||
| - Tmust meet the requirements ofEmplaceConstructiblein order to use overload (4,5). | ||
| - Tmust meet the requirements ofSwappable,MoveAssignable,MoveConstructibleandMoveInsertablein order to use overload (4,5). (since C++17) | ||
[edit] Return value
1-2) Iterator pointing to the inserted 
value
3) 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.[edit] 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.[edit] Exceptions
If an exception is thrown when inserting a single element at either end, this function has no effect (strong exception guarantee).
[edit] 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) |