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unordered_multimap::insert

Inserts an element or a range of elements into an unordered_multimap.

iterator insert(
    const value_type& Val
); // single element

iterator insert(
    const_iterator Where,
    const value_type& Val
); // single element with hint

template<class ValTy>
    iterator insert(
        ValTy&& Val
); // single element, perfect forwarded

template<class ValTy>
    iterator insert(
        const_iterator Where,
        ValTy&& Val
); // single element, perfect forwarded, with hint 

template<class InputIterator> 
    void insert(
        InputIterator First,
        InputIterator Last
    ); // range

void insert(
    initializer_list<value_type> IList
); // initializer list

Parameters

Parameter

Description

Val

The value of an element to be inserted into the unordered_multimap.

Where

The place to start searching for the correct point of insertion.

ValTy

Template parameter that specifies the argument type that the unordered_multimap can use to construct an element of value_type, and perfect-forwards Val as an argument.

First

The position of the first element to be copied.

Last

The position just beyond the last element to be copied.

InputIterator

Template function argument that meets the requirements of an input iterator that points to elements of a type that can be used to construct value_type objects.

IList

The initializer_list from which to copy the elements.

Return Value

The single-element insert member functions return an iterator to the position where the new element was inserted into the unordered_multimap.

Remarks

No pointers or references are invalidated by this function, but it may invalidate all iterators to the container.

During the insertion of just one element, if an exception is thrown but does not occur in the container's hash function, the container's state is not modified. If the exception is thrown in the hash function, the result is undefined. During the insertion of multiple elements, if an exception is thrown, the container is left in an unspecified but valid state.

The value_type of a container is a typedef that belongs to the container, and for map, map<K, V>::value_type is pair<const K, V>. The value of an element is an ordered pair in which the first component is equal to the key value and the second component is equal to the data value of the element.

The range member function:

template<class InputIterator> 
    void insert(
        InputIterator First,
        InputIterator Last
    ); // range

inserts the sequence of element values into an unordered_multimap that corresponds to each element addressed by an iterator in the range [First, Last); therefore, Last does not get inserted. The container member function end() refers to the position just after the last element in the container—for example, the statement m.insert(v.begin(), v.end()); inserts all elements of v into m.

The initializer list member function:

void insert(
    initializer_list<value_type> IList
); // initializer list

uses an initializer_list to copy elements into the unordered_multimap.

For insertion of an element constructed in place—that is, no copy or move operations are performed—see unordered_multimap::emplace and unordered_multimap::emplace_hint.

For a code example, see multiset::insert.

Requirements

Header: <unordered_map>

Namespace: std

See Also

Reference

<unordered_map>

unordered_multimap Class

Standard Template Library